A link without a right, or ubi nexus, ibi jus (?): international human rights instruments & international tax policy

ABSTRACT

In recent years, human rights scholarship has progressively turned its gaze to the topic of taxation. As a growing body of literature has shown, both the tasks of raising and spending tax revenue may impinge on the realisation of socio-economic rights, a relationship here termed tax and human rights nexus. Notably, however, sovereigns' fiscal powers are, to a large extent, curtailed by the international tax regime. Whereas appeals for a normative alignment between international tax law and human rights are mounting, a closer look at what exactly international human rights frameworks allow with respect to taxation is still largely missing. This article seeks to fill this gap by systematically analysing regional human rights court's jurisprudence on taxation where it intersects socio-economic rights. In doing so, it aims at illuminating the opportunities and challenges for human rights judicial review of international fiscal policies.

KEYWORDS:

• Regional human rights systems
• socio-economic rights
• international taxation
• transnational law

1. Introduction

International tax law has organically evolved uninformed by human rights considerations.¹ While reflections on what is fair in matters of international taxation have gradually gained more space in tax scholarship² in recent years, human rights language and normativity have yet to properly seep into fiscal theory and practice. Human rights scholarship, for its part, traditionally fared no better in dedicating much attention to international taxation. The bulk of progress made in unravelling the ties that link and the rifts that separate the two spheres is largely the product of the last decade or so.³ Within that timeframe, a segment of the literature has been permeated by a growing understanding that domestic realisation of human rights, particularly socio-economic rights in developing countries⁴, can be deeply affected by international taxation rules.⁵

As it happens, domestic resource mobilisation can, and often is, significantly constrained by choices and decisions made in spaces outside of the nation-state and beyond many developing countries’ reach.⁶ A burgeoning body of interdisciplinary work now looks at the relationship between tax revenue collection/spending and socio-economic rights realisation—the tax and human rights nexus⁷—from a few different angles.⁸ Accordingly, the need for a rapprochement between the two worlds' underlying structures has become rather apparent. That notwithstanding, a closer look at what exactly international human rights frameworks allow with respect to taxation is still largely missing. Specifically, no structured appraisal has been conducted yet of whether regional human rights frameworks even enable the interpretation that taxation is, in fact, an instrument of socio-economic rights' realisation.

Calls for normative alignment between taxation and human rights, while valuable, can only take us so far.⁹ It is thus of great importance that we consider: do regional human rights legal instruments make the tax and human rights nexus explicit? What (human) right, if any, can be claimed in relation to international tax policy? Are there any judicially established human rights boundaries or principles applicable to fiscal policies at the international level? And, are transnational fiscal relations¹⁰ accounted for in current human rights frameworks? Seeking to address these questions, the present article provides a systematic analysis of regional human rights court's jurisprudence on taxation where it intersects socio-economic rights.

In doing so, it aims to demonstrate that current regional human rights frameworks are not prime candidates for assertion of the tax and human rights nexus, especially from a transnational viewpoint that focuses on developing countries' interests. It further considers alternatives to litigation of the nexus from a domestic and an international tax law perspective. Against this background, the article proceeds as follows. Section 2 examines the challenges and opportunities for judicial review of (international) tax policies within the African, European and Inter-American Human Rights Systems. Section 3 weighs in on the potential for litigation of the nexus at the domestic level. Section 4 discusses avenues (or the lack thereof) for structural change of the international tax regime from within. Section 5 remarks on the inherently transnational nature of the issues covered and Section 6 concludes.

2. International human rights systems and (international) fiscal policy

To acknowledge that taxation intersects human rights¹¹ (and vice-versa) is by all means not the same as suggesting that fiscal policies decided on the international plane can be deemed to be in violation of positive international human rights law.¹² Notably important in determining what may or may not constitute a violation are the actual texts of international human rights instruments and corresponding interpretations provided by regional adjudication bodies in their case law. To be sure, analyses in abstracto of comprehensive frameworks, such as that of the International Covenant on Economic, Social and Cultural Rights (ICESCR),¹³ are instrumental in enabling the identification of guiding principles for the tax and human rights nexus. Equally, the work of specialised quasi-judicial bodies¹⁴ in attributing meaning to such frameworks' wording anticipates what courts' jurisprudence could look like in the future.

Salient as they are, these initiatives are still the tip of the iceberg when it comes to establishing how exactly tax and socio-economic rights interact legally. Yet to be properly explored by scholarship is the suitability of international human rights systems to right some of the structural wrongs of the international tax regime. Conceiving ways to bridge the gap between what is and what should be necessarily begs a diagnostic appraisal of the tools offered by international human rights litigation. Given how far removed from the democratic process they are,¹⁵ political circles of international tax governance could, we argue, certainly benefit from an external nudge by judicial bodies. As the example of climate governance has shown, politically achieving world consensus in the inter-state allocation of responsibilities relies on slow movements of ebbs and flows.¹⁶ Climate litigation has, in this context, become a lever for more expeditious change.¹⁷ It is time we ask ourselves then: can the international tax regime be reined in¹⁸ by international human rights law?

2.1. African system

We first examine the possibilities offered (or inhibited) by the African Human Rights System, the youngest of existing regional systems. The African Charter on Human and Peoples' Rights¹⁹ (also known as the Banjul Charter or ACHPR), the core justiciable human rights instrument within the system, was adopted in 1981 and came into force in 1986. A Protocol to the Charter²⁰ establishing the jurisdiction of the African Court on Human and Peoples' Rights (African Court or ACtHPR) was adopted in 1998 and came into force in 2004. At the time of drafting, thirty-four countries have ratified the Protocol accepting the competence of the African Court. In the past twenty years, the body has delivered almost 400 decisions (between judgments and orders), and fifteen Advisory Opinions.

According to the rules on access to the Court contained in Article 5 of the Protocol, only the African Commission on Human and Peoples' Rights (African Commission), States Parties to the Protocol,²¹ and African Intergovernmental Organisations are entitled to submit cases to its appreciation. States Parties that wish to recognise the Court's competence to process cases filed by individuals and non-governmental organisations (NGOs) must deposit a special declaration indicating such wish alongside the Protocol itself.²² To date, only twelve States Parties have done so, four of which (namely, Rwanda, Tanzania, Benin and Côte d'Ivoire) have since withdrawn their declarations.²³ Such high threshold for legal standing—and, consequently, for jurisdictional access—naturally has an impact on the number (and nature) of cases that can be adjudicated on by the Court. It is against the background of these statistics that one may draw any general conclusions about the ACtHPR's jurisprudence on the tax and human rights nexus.

Unlike its European and Inter-American counterparts, the Banjul Charter explicitly refers to taxes, and implicitly to the social contract, in its main text. Article 29(6) establishes that an individual has the duty ‘to work to the best of his abilities and competence, and to pay taxes imposed by law in the interest of the society’.²⁴ From such straightforward wording the optimists among us would perhaps expect to witness the development of some jurisprudence around the tax and human rights nexus. What, after all, is the link between payment of taxes and society's interests? Rather disappointingly, however, no interpretations of the provision have been given by the African Court thus far, either in contentious cases²⁵ or in Advisory Opinions.²⁶

Looking beyond explicit wording, the contents of Article 21 would appear as perhaps a suitable alternative to enable judicial interpretation of the nexus. Article 21(1) specifically reads: ‘All peoples shall freely dispose of their wealth and natural resources. This right shall be exercised in the exclusive interest of the people. In no case shall a people be deprived of it’.²⁷ Paragraph 5 subsequently stipulates: ‘States Parties to the present Charter shall undertake to eliminate all forms of foreign exploitation particularly that practised by international monopoles so as to enable their peoples to fully benefit from the advantages derived from their national resources’.²⁸ A systematic and teleological interpretation of these provisions leads to the tentative conclusion that wealth and natural resources management should be normally associated with the broader objective of socio-economic empowerment of the African peoples.

To the extent that those in charge of wealth and natural resources management, namely government, can be said to have the (corresponding) duty to administer these with the exclusive interest of their peoples in mind, the limits to discretion in tax policy delineation could arguably be examined within this provision's frame. As a policy instrument, taxation can be shaped to pursue different goals (including an equitable distribution of wealth) and leveraged in countless different ways to ensure that social benefits can be collectively reaped from natural resources' usage. Specifically, it can be designed to, among other things: directly capitalise on the exploitation of natural resources (eg, via royalties and/or withholding taxes as may be appropriate); disincentivise behaviour that may lead to the depletion or degradation of natural resources (eg, via carbon taxes); promote actions that aim to protect the integrity of natural resources (eg, via tax credits/rebates for environmentally sustainable businesses and households), etc.

The pressing question would then be whether the right of (free) disposition mentioned in Article 21(1) strictly relates to aspects of ownership/possession—ie, a people, through its government, may sell public property, use a body of water or cede mineral rights to private actors, for example—or whether it also encompasses broader elements of public finance management. As previously observed, the wording of Article 21(5) does seem to buttress the interpretation that the right should be seen as a means to an end—the end being a people's full enjoyment of the benefits derived from their national resources. That being the case, a reasonable argument could be made that, where they relate to wealth and natural resources management, fiscal policies should be geared towards attaining collective welfare.

Despite these latent avenues for clarification, the ACtHPR's case law has sadly not evolved in that direction yet. In reality, cases in which Article 21 has been legally invoked by applicants are still very few. In the paradigmatic case African Commission on Human and Peoples' Rights v. Republic of Kenya,²⁹ for example, an alleged violation of the provision was reviewed against the backdrop of discussions on land ownership. The case concerned, in sum, the eviction of the Ogiek people from their ancestral lands in the Mau Forest. While the Court did not provide a thorough interpretation of Article 21’s contents, the case does offer an interesting, albeit small, insight into the relationship between socio-economic rights realisation and the need for funding mechanisms of a collective character. As the ACtHPR found Kenya to be in breach of its human rights obligations, it ordered as part of reparations³⁰ the establishment of a community development fund on behalf of the Ogiek people. As determined, the fund is to ‘be used to support projects for the benefit of the Ogiek in the areas of health, education, food security, natural resource management and any other causes beneficial to [their] well-being’.³¹

The notion that financial compensation for the Ogieks' wrongful eviction should be used to further socio-economic rights—actually denied because of their expulsion—leaves room for important considerations. For instance, due to the provision's inherently economic (‘wealth and natural resources’) and collective (‘interests of the people’) nature, should future declarations of a violation of Article 21 automatically lead to the establishment of a community development fund? And how do these types of funds conceptually differ from a regular compensation order? Could the Court go further in specifying that, in channelling public monies into community development funds, governments should not simply divert funds that would have otherwise been allocated to initiatives that promote socio-economic development? Questions like these remain woefully open at the regional level and, while they may seem farfetched at present, legally defining the tax and human rights nexus necessarily depends on finding adequate answers to the challenges they reveal.

That said, whereas the ACtHPR may be the central judicial body within the African Human Rights System, it is not the only court in the continent vested with jurisdiction to rule over human rights issues.³² As it turned out, another (sub-)regional court whose mandate is not primarily³³ circumscribed to human rights' protection was the one to lay some groundwork on the subject at hand. In National Co-ordinating Group of Departmental Representatives of the Cocoa–Coffee Sector (CNDD) v Co^te d'Ivoire, the Court of Justice of the Economic Community of West African States (ECOWAS Court) asserted its jurisdiction over claims of human rights violations emphasising that these ‘may occur in any sector governed by national law, be it on taxation law or otherwise’.³⁴ While noting that ‘in the area of taxation, States have a large margin of operation’³⁵, it highlighted that international bodies, including itself, have a right ‘to examine the legitimacy of the legal stance adopted by the States and their proportionality with the aims and objectives of guaranteed [human] rights’.³⁶ In the Court's view, states should not use their margin of freedom to enact national legislation that ‘end[s] up emptying [human] rights or freedoms of the very essence of their meaning’.³⁷

In brief, the case was born out of the applicant's claim that excessive taxation on raw cocoa and coffee eroded the purchasing power of its membership (ie, these commodities' producers). As argued by the applicant, this in turn violated the producers’ right to a just and fair remuneration as prescribed by Article 23(3) of the Universal Declaration of Human Rights. The case additionally rested on the applicant's understanding that the comparatively lighter tax burden imposed on producers from Ghana and Nigeria by their respective governments constituted a violation of the principle of equality of all citizens before the law. As noted, the ECOWAS Court was of the opinion that government policies in general were subject to judicial review, including those related to taxation.

Ultimately, though, it found that Côte d’Ivoire was under no obligation of a just and favourable remuneration towards the applicant's membership as no employment relationship between applicant and defendant existed. It also held that no violation of the principle of equality of all citizens before the law could be found given the lack of comparability between cocoa/coffee producers in Côte d'Ivoire and those based abroad. In this regard the Court relied on its own precedent to emphasise that ‘equality presupposes same treatment of persons placed in same situation, and that in salary matters, the principle of equality may not be invoked when the source of remuneration is not the same’.³⁸

The judicial organ further pointed out that equality does not preclude differentiated treatment per se as long as the situations presented are intrinsically different, or the differentiation at hand is aimed at ‘reducing disparities or inequalities’.³⁹ The judgement briefly illustrated the argument indicating that levying different taxes on different agricultural products might be justified by policy or aspects particular to the products themselves. Following that reasoning, it hinted at a potentially more suitable basis for the applicant's claim of unequal treatment using the example of government subsidies in the cotton industry in West African countries. That is, that the inequality claim could have been grounded on existing differences between taxes levied by the Ivorian government on cocoa/coffee as compared to cotton.

One of its kind, the ruling sparks complementary considerations. While it can be praised for leaving the door open for future review of domestic tax legislation that may collide with human rights commitments in the (sub-)region, it can also be criticised for the rather narrow analysis presented. Far from yielding a comprehensive legal interpretation of the tax and human rights nexus in the (West) African context, this example demonstrates one of the main difficulties of litigating justice-related claims,⁴⁰ which is adequately framing them within the provisions of applicable legal sources.⁴¹ Given that the jurisdictional activity is mostly bound by the wording of relevant legal instruments⁴², finding the right angle—ie, a specific legal right—to submit a case that encapsulates the nexus can be a challenge in and of itself.⁴³

That the ECOWAS Court held that an employment relationship was indispensable for the right to fair and favourable remuneration to apply is not illogical. Similarly, the reasoning that a potential violation of the principle of equality can only be determined for individuals in a situation deemed comparable is not legally unsound. But neither of these points addresses the underlying problem presumably faced by the applicant's membership: an onerous tax burden that further pushes already impoverished communities into deeper socio-economic distress. They also fail to illuminate what a human rights compliant tax policy could look like, both in terms of how tax revenue is raised and spent.

Aside from availing of the principle of iura novit curia—which is particularly well-established in the domain of human rights protection⁴⁴—to look beyond specific legal arguments raised by the parties,⁴⁵ the Court could have arguably dug deeper into the ensconced aspects that the lawsuit clearly contained. For example, it could have engaged in a more detailed examination of whether the introduction of nuance (or progressivity) in tax policy flows from the principle of equality. In that sense, a few lines of reasoning could have been dedicated to discussing whether all producers of one specific commodity within a given country should pay the same applicable tax rate regardless of elements such as their legal nature or size (if incorporated). Without getting into the technicalities of defining tax rates, the Court could have taken the opportunity to dissect some guiding principles it deemed relevant for the topic under exam. The need for counterweight (social) measures to mitigate excessive tax burdens within governments' taxation legal frameworks could have also been the object of further inspection.

One important observation to be made is that the case discussed evidently revolves around a vertical relationship between a country and its own nationals/residents. Even cross-country comparability between producers of the same commodity was ruled out by the ECOWAS Court in this particular case. In the same vein, Article 29(6) of the Banjul Charter seems to account for the social contract only from a domestic perspective. The provision determines that taxes must be paid in the interest of the society but the limits and scope of the term society are still widely undetermined. Therefore, transnational relationships that may exist between a national/resident of one country and the international tax regime more broadly, or between the former and tax policies with extraterritorial effect enacted by another country do not fit prima facie the litigation frameworks that the provision and the ruling offer. But, relevantly, any particular rights and/or links that can be gleaned from jurisdictional interpretations in a domestic vertical setting can be used as a starting point for legal extrapolation in a transnational setting.

2.2. European system

The next regional system to be considered is the European Human Rights System whose case law dates back to the 1950s. With the clear advantage of permitting direct individual⁴⁶ (and corporate) access to the European Court of Human Rights (European Court or ECtHR), the system has become a remarkable repository of interpretative guideposts in a myriad of human rights issues.⁴⁷ While its main legal instrument, the European Convention on Human Rights (European Convention or ECHR), aims at protecting, first and foremost, civil and political rights, the ECtHR has long held that no watertight division separates such first generation rights from economic and social rights.⁴⁸ Congruently, the ECtHR has steadily developed case law that gives effect to rights not explicitly safeguarded by the ECHR⁴⁹ but that are broadly connected to the idea of a minimum core of socio-economic protection.⁵⁰

Over the years, the Court's inclination to expand the breadth of rights' protection in Europe has, on the one hand, been pegged as judicial activism⁵¹ and, on the other, vehemently defended as a much needed expression of evolutive interpretation.⁵² It makes a good degree of sense then that the ECtHR would find a relatively convoluted, potentially controversial,⁵³ way to expand on the link between taxation and socio-economic rights. The ECHR does not make any references to the word(s) tax and/or fiscal in its main text. Article 1 of Protocol No. 1⁵⁴ to the ECHR, however, conspicuously links taxes to the right to private property. As a civil and political rights instrument, this is hardly surprising. Through the prism of individual freedoms, taxes fundamentally constitute an encroachment on someone's private sphere and connected possessions. In social liberal democracies the encroachment itself is not generally disputed but rather its degree or extent.

Due to its broad wording, Article 1 of Protocol No. 1 became a staple for litigants wishing to impugn a vast set of measures that are not always, or necessarily, related to the state's fiscal authority. Because it primarily regulates interference with the peaceful enjoyment of one's possessions the provision readily lends itself to discussions such as: what does possession mean?; what characterises deprivation?; what can be understood by (a justifiable) public interest?; etc. In addressing these questions, the Court has not only upheld the right to private property in more traditional cases, where possession is seen as an existing object⁵⁵ (res), but also progressively clarified that a legitimate expectation of obtaining an asset⁵⁶ can fall within the protection accorded by the Protocol as well.

It follows that the ECtHR's case law that does zero in on matters of taxation and socio-economic rights has, by and large, dealt with situations where individual and corporate taxpayers attempt to repel or restrain the state's fiscal appetite.⁵⁷ In other words, applicants usually seek to review decisions taken by national fiscal authorities that, in their eyes, resulted either in excessive taxation or inadequate reimbursement of taxes paid.⁵⁸ That is not to say, in any event, that the multifaceted topic of taxation has only come under the ECtHR's scrutiny where it pertains to private property. Additional claims based on how fiscal measures may violate other rights protected by the ECHR, such as the right to respect for private and family life⁵⁹ (Article 8) and the prohibition of discrimination⁶⁰ (Article 14), have also arisen before the Court.

But, rather interestingly, it has been through a generous interpretation of the different elements that make up the contents of Article 1 of Protocol No. 1 that the ECtHR has firmly expanded the ECHR's material reach to the realm of social protection.⁶¹ As we seek to identify patterns of judicial interpretation that frame taxation as an instrument of socio-economic rights realisation, case law developed in connection with Article 1 of Protocol No. 1 better aligns with our purposes. It should be noted, however, that providing an exhaustive overview of all case law connected to taxation under this provision is well beyond the scope of this article.⁶² Rather, the present exercise aims at shedding a light on the extent to which the ECtHR has settled on any principles that must steer state conduct in the design and implementation of fiscal policies that may impinge on the minimum core of socio-economic protection.

Sieving through judicially established boundaries for the exercise of fiscal power helps in determining four equally important aspects. First, it aids in revealing where the European Court stands when it comes to reviewing tax policy (ie, under what circumstances is it possible, if at all?). Secondly, it enables a better grasp of the tax and human rights nexus vis-à-vis the ECHR's ambit of application and the degree of social protection accorded by different domestic legislations. Thirdly, it elucidates the extent to which the Court has been willing to engage with broader analyses of structural problems caused, wholly or partly, by economic and fiscal policies. Finally, it clarifies some of the hurdles for any litigation that goes beyond the assertion of negative rights and seeks, instead, recognition of litigants' positive rights.

To begin with, the European Court has very clearly and frequently stated that Article 1 of Protocol No. 1 comprises three distinct but interconnected rules.⁶³ The first rule sets out the principle of peaceful enjoyment of property; the second makes the deprivation of possessions conditional on certain criteria; and the third recognises states' prerogative to limit, through the enforcement of laws, the use of property in accordance with the general interest. Within this framework, the third rule generally confers a priori legitimisation to taxation as long as it meets a few requirements laid down by the Court in its case law.⁶⁴ These interlocked rules, as construed by the ECtHR, also mean that no harsh lines demarcate where debates of enjoyment of private property end, and those centred on the minimum core of socio-economic protection begin. This is important because relevant case law for the tax and human right nexus emerges from a progressive collage of indirect links between the concepts of private property, social protection, subsistence minimum⁶⁵ and fiscal policies.

With respect to social and economic policies,⁶⁶ the European Court has repeatedly affirmed that ‘domestic authorities are in principle better placed than an international court to evaluate local needs and conditions’.⁶⁷ Accordingly, it has sedimented the understanding that the state is usually allowed a wide margin of discretion in relation to general measures of economic or social strategy⁶⁸ such as taxation.⁶⁹ This range of discretion allows states, for example, ‘to decide whether or not to have in place any form of social security scheme’⁷⁰ as ‘Article 1 of Protocol No. 1 does not create a right to receive social benefits or pensions’.⁷¹ However, as stipulated by the Court, ‘legislation in force which provides for the payment as of right of a welfare benefit—whether conditional or not on the prior payment of contributions’⁷²—generates a proprietary interest within the provision's meaning to those who satisfy its domestic requirements. This goes to show that a state's margin of discretion, while ample, is not unlimited.⁷³

The Court has thus delineated a few gatekeeping rules that determine whether judicial review of a state's action is warranted or not. First off, any state interferences with the peaceful enjoyment of possessions must be lawful and compatible with the rule of law.⁷⁴ The requirement of compatibility with the rule of law is particularly noteworthy as the concept is notably broader than that of mere legality.⁷⁵ Secondly, interferences must be justified by a legitimate public (or general) interest which is to be determined by the competent legislature and only judicially scrutinised in case it is manifestly without reasonable foundation.⁷⁶ The ECtHR has already clarified that ‘the notion of “public interest” is necessarily extensive’.⁷⁷ Therefore, different policies—for example, those aimed at protecting the public purse, adapting to socio-political regime changes, reallocating scarce funds and addressing major economic crises through austerity measures⁷⁸—can, in principle, fall within the scope of the public interest. But as the state's margin of discretion is not unfettered, the proportionality of such measures is still susceptible to the Court's inspection.⁷⁹

And so thirdly, state interferences must strike a fair balance between the interests of the community and the protection of an individual's fundamental rights.⁸⁰ In social security related cases, such as those involving claims of wrongful taxation of applicants' pensions, the Court will try to determine whether chosen means of interference resulted in the imposition of an excessive individual burden.⁸¹ Relevantly, the extent of the interference's impact with one's subsistence means and living standards is an important weighing factor in the proportionality assessment.⁸² Fourth and finally, the ECtHR has recognised the existence of procedural rights that must be observed by the state during the process of tax collection. In that regard, the Court held that an ‘interference cannot be legitimate in the absence of adversarial proceedings that comply with the principle of equality of arms, enabling argument to be presented on the issues relevant for the outcome of a case’.⁸³

From the foregoing, it is possible to conclude a few things. In line with what is to be reasonably expected from a supranational adjudication body, the ECtHR adopts a rather hands-off approach when it comes to evaluating economic⁸⁴ and tax policies. This is particularly true for cases that seek judicial review of the social impact of austerity measures.⁸⁵ Such hesitance is quite telling of the Court's deference to the principles of subsidiarity⁸⁶ and separation of powers—although state arguments invoking the latter are not always successful.⁸⁷ But what is more, this brief jurisprudence review provides an insight into the challenges of disputing the general effects that tax policies can have on the minimum core of socio-economic protection using the scaffolding of a civil and political rights instrument.

As seen, the possibility of legal action only arises if the applicant is able to pinpoint a specific interference with their right to peaceful enjoyment of possessions. Litigation is ipso facto circumscribed to the vindication of negative individual rights. By extension, the principles developed by the European Court around taxation and socio-economic rights are mostly adequate for situations where a claim may be sufficiently isolated from broader systemic change of (domestic) fiscal policies. In other words, individuals who are singularly or collectively—due to a specific targeting of an identifiable group they belong to (eg, civil servants, pensioners)—affected by a fiscal measure can, in theory, claim victim status before the ECtHR and avail of the principles established. On the other hand, structural implications of tax policies which are broadly designed or implemented in prejudice of certain socio-economic rights can hardly be contested within this framework.

Suppose, for example, that a given government decides, as a matter of tax policy, to implement cuts to social spending—say, on social housing initiatives—due to broader allocation decisions that are part and parcel of tax policy design—say, a previously adopted decrease in corporate taxes which led to the need for an increase in tax revenue collection elsewhere as compensation. An applicant who could not benefit from social housing due to these cuts could perhaps manage to establish a causal link between the fiscal measure and the resulting harm to their minimum core of socio-economic protection. However, owing to tax policy's fundamental distributive nature the claim itself would be intrinsically collective in terms of its potential outcomes (hence non-individualizable). That is, the Court would hardly be able to rule in favour of the applicant without confirming that, while not directly targeted at them, cuts to social spending indeed resulted in a violation of their protected right. In addition, under the current case law paradigm, the suspended/discontinued social housing initiative would first have to be deemed a possession under Article 1 of Protocol No. 1 before the ECtHR could rule on whether a disproportional state interference had taken place.

It follows that, in order to surpass the set threshold for judicial review of fiscal policies, the applicant would need to somehow ring-fence their claim from broader societal implications so as to reassure the European Court that an ample consideration of the appropriateness and proportionality of cuts to social spending was not needed. But this would of course be extremely difficult to achieve as the claim brought forward would, even if unintentionally, encapsulate the interests of an entire segment of society⁸⁸ that is usually problematic to define in precise legal terms (ie, the most economically vulnerable, the poorest, etc.). Distinctly, this stands in contrast with what is generally observed in claims against other types of enacted (non-economic) policy, particularly those concerning discriminatory measures. While decisions on these cases may engender far-reaching social transformation, claims ought to be framed within well-demarcated protected grounds. Individualisation of claims via priorly defined legal categories allows for a conscious and deliberate exercise of the adjudicatory function. Conversely, claims that are particularly difficult to individualise because of their collective nature are (understandably) bound to give rise to a more cautious judicial approach.

In the end, in the ECHR's wording, taxation is not deemed a funding instrument for the realisation of socio-economic rights but rather a coercive measure that limits private property. Without much room for manoeuvre the ECtHR has admirably succeeded in developing progressive case law that guides states' fiscal action vis-à-vis individually considered persons, thereby protecting their minimum core of socio-economic protection. But simultaneously the Court has all but deferred any true assessment of the tax and human rights nexus and connected principles. Those who may have had their socio-economic rights harmed by tax policies in a non-individualizable way (with regards to the claim itself) cannot count on the Court's jurisdiction for redress.⁸⁹

Admittedly, none of this is especially surprising, given that intrinsically collective claims which seek assertion of a positive right may, in a way, function similarly to claims that aim for a review of policy in abstract terms. As the European ‘Convention does not provide for the institution of an actio popularis’,⁹⁰ the ECtHR's has repeatedly affirmed that ‘its task is not normally to review the relevant law and practice in abstracto’.⁹¹ Beyond paying homage to the separation of powers, the Court's deferential position inadvertently leaves a vacuum of interpretation and, consequently, of human rights protection.⁹² Its overreliance on the domestic democratic process as justification for a hands-off approach⁹³ acutely ignores that not all economic decisions can be independently taken by the domestic state.⁹⁴ Often times policies can be developed in spite of domestic democratic processes⁹⁵ not endorsed by them.⁹⁶

As it holds itself to a higher degree of accountability than some domestic authorities in charge of fiscal policies do, the ECtHR passively misses the opportunity⁹⁷ to provide much needed guidance on the tax and human rights nexus. In that sense, the analysis suggests once again that existing legal frameworks—be it the ECHR or the ECtHR's jurisprudence—do not support the vindication of rights that may plausibly emerge from transnational relationships. Although the Court has developed extensive case law on the application of the ECHR to extraterritorial conduct of Member States, the critical issue of policy measures that have extraterritorial effects, for example, has largely gone unnoticed.⁹⁸ For the European Court, fiscal policy is a legitimate tool that begins and ends within national borders and that, therefore, should only be dissected in extreme cases of excessive curtailment of private property.

It is interesting, then, to note that the interplay between the national and international fiscal domains was vaguely alluded to in a case completely unrelated to tax policy. In his concurrent opinion in N.D. and N.T. v. Spain (which concerned the expulsion of aliens from a Member State's territory), Judge Pejchal emphasised that it was the fulfilment of fiscal —duties and subsequent payment of contributions by Member States that enabled the existence of the European Human Rights System. As a matter of fairness, the judge submitted, fulfilment of fiscal duties should precede a claim for protection of rights under regional human rights systems. Additionally, a preferred order of fiscal allegiance was succinctly spelled out. A brief excerpt of the opinion is worth transcribing:

The application was lodged by citizens of two African States which are not amongst the member States of the Council of Europe and have not acceded to the Convention (and cannot do so as they are not European States). Accordingly, both applicants claimed protection of fundamental rights and freedoms that are guaranteed by a community of free citizens of other States on another continent. Citizens of this (European) community fulfil their fiscal duties vis-à-vis their home countries, member States of the Council of Europe, which use the taxes thus collected to pay their contributions to the Council of Europe, including the European Court of Human Rights. The fulfilment of fiscal duties and the payment of contributions by the member States to the Council of Europe are the prerequisites for the very existence of the European human rights protection mechanism for everyone. It appears that neither of the applicants fulfils his basic duties (including fiscal ones) derived from Article 29 of the African (Banjul) Charter on Human and Peoples' Rights (…). Both States of which the applicants are citizens have ratified the African (Banjul) Charter on Human and Peoples' Rights. From the point of view of general fairness, it must therefore necessarily be assumed that the applicants find themselves in an exceptional situation that renders it justifiable for them not to fulfil their essential duties vis-à-vis their home country and their continent. Only if such an exceptional situation exists is it possible to imagine that the applicants could claim protection of fundamental rights and freedoms guaranteed by a community of free citizens of other States on another continent.⁹⁹

While not representative of the full Court's view, the opinion throws into stark relief the institution's sheer unwillingness to expand on the tax and human rights nexus as it demonstrates that some of the nexus' underlying links are not too implausible or absurd to be legally discussed and eventually defined.

2.3. Inter-American system

The remaining regional system to be examined is the Inter-American Human Rights System, born with the adoption of the Charter of the Organization of American States¹⁰⁰ (OAS) in 1948. Its main actors,¹⁰¹ the Inter-American Commission on Human Rights (IACHR or Inter-American Commission) and the Inter-American Court of Human Rights (IACtHR or Inter-American Court), were respectively established by the OAS Charter and the American Convention on Human Rights¹⁰² (Pact of San José or ACHR). The latter was adopted in 1969 and came into force in 1978. In many ways, the Inter-American System sits somewhere in between the two previously covered ones.

Much like the African system, it precludes, as a rule, direct individual access to the IACtHR. Petitions communicating alleged violations of rights must be lodged¹⁰³ instead with the Inter-American Commission which may or may not submit a case to the Court in accordance with internal procedures.¹⁰⁴ States Parties to the ACHR may also submit cases to the IACtHR provided that they have accepted the Court's competence.¹⁰⁵ Notably absent from the list of countries that have accepted the IACtHR's jurisdiction are Canada and the United States of America (USA). The central legal instrument of the Inter-American System, the ACHR, is an eminent civil and political rights diploma which more closely resembles that of the European System. However, unlike the latter, the ACHR makes literal reference to the protection of socio-economic rights in its main text.

Article 26 borrows the language of the ICESCR to establish an obligation of progressive realisation of socio-economic rights that are implicitly contained in the OAS Charter. A truly unique feature of the ACHR, this referencing of the Charter allows for a significant widening of the Court's jurisdictional reach ratione materiae.¹⁰⁶ Such porousness between the two instruments enables many angles of judicial interpretation and legal enunciation of the tax and human rights nexus. Whatever the ACHR may lack in legal substratum for interpretation, the Charter can theoretically make up for in expandable content. For example, the Convention's text does not contemplate the word tax at all.¹⁰⁷ But that void is filled by the Charter which expressly mentions the term in connection with key concepts of the tax and human rights nexus (eg, elimination of extreme poverty, equitable distribution of wealth and income, and participatory decision-making¹⁰⁸).

Through Article 34(c) OAS Member States have pledged to accomplish the basic goal of having adequate and equitable systems of taxation in place which per se is fairly remarkable. The provision's added dimension of equity clearly exceeds the texts of other international human rights instruments where they pertain to taxation. To an extent, it even goes beyond what is routinely seen in domestic constitutional frameworks.¹⁰⁹ The traditional notion of fiscal federalism adopted in Western countries is notably minimalistic in that it mostly relies on constitutional texts to merely distribute taxing powers among government tiers.¹¹⁰ The OAS Charter, on the other hand, explicitly qualifies equitable systems of taxation as a means to achieving, inter alia, the elimination of extreme poverty.

Very clearly such wording could well constitute the embryonic nucleus of the tax and human rights nexus. But, mirroring the African experience,¹¹¹ no contentious cases before the IACtHR have dealt with the specific constructs of Article 34(c) yet. Their sole existence in a binding legal instrument, however, bodes well for future clarification, particularly in light of the Court's recent case law expanding on other points of Article 34 such as (g) on the right to fair working conditions¹¹² and (j) on the right to adequate food.¹¹³ These developments are, it must be said, part of a visibly larger trend in the IACtHR's jurisprudence whereupon, in the last few years, an increasing number of decisions recognising violations of socio-economic rights have been handed down.

Notably, it was only in 2017¹¹⁴, in Lagos del Campo v. Peru,¹¹⁵ that the IACtHR inaugurally found that socio-economic rights derived from Article 26 of the ACHR were directly and autonomously justiciable. Nothing short of ground-breaking, this recognition could, in principle, pave the way for a relatively clear path of litigation of the tax and human rights nexus. As noted earlier with respect to the ECtHR's case law, litigation of the nexus can be sorely restricted by a civil and political rights instrument that requires issue-framing vis-à-vis negative state duties. Importantly, though, it is not just that the Inter-American Court has not analysed, to date, the specificities of Article 34(c). More broadly, it has not yet been provoked to utter in a concrete case any considerations on applicable human rights boundaries to fiscal policies. If cast against the background of the region's history with neoliberal policies¹¹⁶ that, beyond unpopular, drove several million people into a life below the poverty line, this seems counter-intuitive. Measures of fiscal consolidation and austerity in particular have been successively adopted by a handful of Latin American governments over the last thirty years.

So how can it be that structural challenges to these policies are not reaching those at the helm of human rights adjudication in the region? A fair point has been raised in scholarship that many austerity measures are implemented via ‘constitutional amendments that put a ceiling on fiscal expenses, which collides with the expansion of social expenses emerging from the enforcement of socio-economic rights’.¹¹⁷ Because such measures become constitutionally enshrined norms they ‘may impose a constitutional limit to the IACtHR's influence … and impede its agenda of transforming the deep economic structures in the region via constitutional adjudication’.¹¹⁸ But this offers only partial explanation for the lack of cases objecting fiscal measures on the IACtHR's docket. Building on this point, we argue that one special feature of the Inter-American System, and one intrinsic quality of the subject at hand provide a more nuanced account of the reasons behind the phenomenon.

Firstly, the IACtHR is known for embracing a markedly proactive attitude in interpreting the ACHR, particularly if compared to the European Court's stance.¹¹⁹ As elucidated in the previous section, the margin of appreciation doctrine is widely employed by the ECtHR to pay deference to national authorities' and domestic courts’ autonomy. The IACtHR, on the other hand, has long leaned on its doctrine of conventionality control¹²⁰ to assert the ACHR's precedence over non-conforming constitutional provisions, and to bestow on national courts a duty of conventionality review.¹²¹ In that sense, constitutional protection of certain fiscal policies would not, in and of itself, preclude the IACtHR's competence. But a diffuse model of judicial review may, by extension, lead to situations where national courts deliver judgements on certain subjects ‘before the [Inter-American] Court has the chance to do so’.¹²²

Secondly, as previously noted, cases only reach the IACtHR after being analysed by the Inter-American Commission following its own special procedure. But, importantly, both organs have already clarified that petitions in abstracto cannot be processed by the Inter-American System.¹²³ As argued elsewhere in this article, individualising¹²⁴ claims that are, in fact, the embodiment of broader socio-economic consequences of tax policies could prove to be a tricky endeavour for petitioners. In light of similar conclusions reached in relation to the European System, a pattern of foreclosing litigation of the tax and human rights nexus at the international level seems to emerge.

All that said, it is imperative to acknowledge that the IACtHR has already begun providing important markers of interpretation in the sphere of socio-economic rights that may be relied upon in the future to legally articulate the nexus. In Muelle Flores v. Peru,¹²⁵ it affirmed for the first time that a specific right to social protection could be derived from the wording of Article 26 of the ACHR. The Court was relatively thorough in defining the constitutive elements of the right indicating that it ‘seeks to protect the individual from future contingencies that, should they occur, would have harmful consequences for that person’.¹²⁶ It further observed that ‘social security must be implemented in a way that guarantees conditions that ensure life, health and a decent economic status’.¹²⁷ The adjudication body went as far as enumerating state obligations with respect to the implementation of pension schemes,¹²⁸ pointing out, rather notably, that the defendant state should ensure that contributions towards a scheme were affordable. Emphasising that the right to social security attracted obligations of an immediate nature as well as those of a progressive realisation nature, the Court ratified its well established case law of non-retrogression of realisation of rights achieved.

This exact interpretation of the right to social security was subsequently repeated in National Association of Discharged and Retired Employees of the National Tax Administration Superintendence (ANCEJUB-SUNAT) v. Peru.¹²⁹ Here, however, the Court very evidently attempted to temper some of the bolder jurisprudential contours established in Muelle. In a clear effort to deflect potential criticism of its reasoning, the IACtHR thought it prudent to clarify that ‘it is not assuming competences with regard to treaties for which it does not have them, and it is not granting Convention rank to provisions contained in other national and international instruments relating to the economic, social, cultural and environmental rights’.¹³⁰ Rather, the Court observed, the interpretation given was well within the bounds of Article 29 of the ACHR, and ‘in accordance with its jurisprudential practice, which allows it to update the meaning of the rights derived from the OAS Charter that are recognized by Article 26 of the Convention’.¹³¹

While neither of these cases delve into the specifics of financing (the right to) social security, they arguably point towards the existence of very early signs of jurisprudential recognition of the tax and human rights nexus. For instance, it seems reasonable to suggest that, according to the IACtHR's case law, affordability of social contributions' payments should be one guiding aspect of governments’ fiscal policies. Whether affordability should be an obligation of result or means¹³² could be the object of further jurisprudential scrutiny in the future. Beyond that, it also seems safe to infer that national budgets must take into account that the minimum amount paid by pension schemes should be enough to ensure a decent economic status to pensioners. The establishment of an obligation of periodical revision of pension thresholds could perhaps be discussed by the Court in follow up cases.

In that vein, the IACtHR has already spoken on the requirement of (financial) accessibility in relation to the right to health. In Cuscul Pivaral et al. v. Guatemala the Court was asked to assess whether the state had violated the applicants' rights to health, life and personal integrity through a lack of provision of public medical care that was compatible with the applicants’ status as individuals living with HIV/AIDS. The Court then observed that ‘[T]he element of accessibility requires that the health care facilities, goods and services are accessible, in law and in fact, for the most vulnerable and marginalized sectors’.¹³³ Interestingly, not only did the IACtHR find the state to be in violation of its human rights obligations but also deemed ‘appropriate to order as a measure of satisfaction that the State grant scholarships in public establishments to those victims whose personal development has suffered as a result of human rights violations’.¹³⁴ The idea that reparation for state omissions (or harmful actions) in the socio-economic realm should also come in the form of specific financial arrangements that enable the realisation of socio-economic rights¹³⁵ is intimately related to the tax and human rights nexus.

Notwithstanding such incipient evidence of the Court's tendency to slowly develop case law around the nexus, it is important to highlight that these lines of reasoning are quarrelsome even amongst those sitting on the bench. In his partially dissenting opinion in Cuscul, for example, Judge Humberto Antonio Sierra Porto partly opposed the Court's majority ruling essentially grounding his arguments on the margin of appreciation doctrine.¹³⁶ Even so, there is no denying that an increasing amount of voices within the Court are willing to engage in creative argumentation to better delineate state obligations with respect to socio-economic rights. In his concurring opinion in Guevara Díaz v. Costa Rica, Judge Rodrigo Mudrovitsch reflected over what the Court's role should be in cases of collective or mass human rights violations which occur because of political obstacles or institutional failings. In his view, the IACtHR should administer dialogical remedies ‘by assigning responsibilities and finding a need for economic and fiscal planning to implement the right withheld (in the case of an omission) or provide reparations (in the event of an action that amounts to a rights violation)’.¹³⁷ The establishment of continual dialogue between the Court and Member States, he added, should be the focus of compliance structures going forward.

One final and brief remark about transnational litigation of the tax and human rights nexus before the IACtHR is due. The outlook here is decidedly more positive than the one observed for the other two regional systems. Article 35 of the OAS Charter stipulates that ‘Member States should refrain from practicing policies and adopting actions or measures that have serious adverse effects on the development of other Member States’.¹³⁸ A systematic interpretation of this provision in tandem with the contents of Article 34(c) could, in principle, enable considerations about domestic fiscal policies which transnationally affect peoples' of other Member States. On the other hand, the provision clearly falls short of covering relationships between Member States and non-Member States, as well as broader policies embedded in the international tax regime.

2.4. Interim conclusions: unconforming tax policies as a human rights issue, not a human rights violation

With sporadic silver linings, this survey of regional human rights courts' jurisprudence on the tax and human rights nexus points to a rather discouraging picture. Challenging fiscal policies on the basis of the negative impacts they may have on socio-economic rights via international (regional) human rights litigation is thwarted on a few different grounds. Most notably, two out of three regional human rights frameworks do not create, or support, a straightforward juridical link between taxation and socio-economic rights realisation—precisely the core of the nexus. These instruments' wording reveals nothing (ECHR) or nearly nothing (Banjul Charter) about states' (presumed) responsibilities of raising (and spending) tax revenue in a human rights compliant manner.

While the ECHR frames taxation as an interference with individual freedoms, the Banjul Charter establishes an individual obligation to pay taxes but remains silent about any corresponding fiscal duties on the part of the state. On the other hand, where permissive provisions theoretically enable legal enunciation of the nexus (ACHR; OAS Charter), the respective court's power is yet to be galvanised. But whether the nexus gets to be outlined via jurisprudential interpretation¹³⁹ or not widely rests on the extent of procedural rules on jurisdictional access. Indeed, the lack of a precise legal definition of the nexus distinctly results in greater difficulty for petitioners to demonstrate legal standing as victims of a human rights violation. In the African and Inter-American contexts in particular, individual petitioners first need to show locus standi within their respective Commissions' procedures before the matter can eventually reach regional courts. In this scenario, judicial appreciation of the nexus seems ever less likely.

Moreover, claims in abstracto are generally not admissible before the examined courts. Consequently, and again as a matter of admissibility, petitioners are expected to demonstrate that a given tax policy has concretely affected a particular socio-economic right in an individualizable manner (as in, susceptible to isolation from broader systemic change) before a court can look into arguments of substance. But, by their very (distributive) nature, tax policies are, by and large, meant to be general¹⁴⁰ and collective. In the European case, there is the added challenge of properly framing claims of socio-economic rights' violations using a civil and political rights instrument as framework of reference.

Against this backdrop, it seems unlikely, for example, that civil society organisations that possess both fiscal and human rights expertise would be able to litigate the nexus before regional human rights courts. Presumably, only associations that have some representative capacity of a group or collective would be able to (potentially) fulfil legal standing criteria. Finally, where courts have been confronted with matters relevant to the nexus (ECHR, ECOWAS Court) recourse to judicial deference has essentially dampened any meaningful advancement of its legal contours. In the end, the misconception that every relevant aspect of tax policy design and implementation still falls entirely within the purview of the domestic democratic process seems to only work against the realisation of socio-economic rights around the globe.

The many obstacles to litigation of the nexus can thus be summarised as: the predicament to neatly triangulate, or combine, the relevant aspects of wording, standing and framing in one single suit. To put it differently, litigation of the nexus can theoretically succeed if a legal instrument frames taxation as a tool for socio-economic rights realisation and provides specific-enough wording from which to derive a legal entitlement while making connected legal standing rules more flexible. These conclusions are particularly important if interpreted against this article broad aspirations of uncovering judicially established human rights principles for the tax and human rights nexus at the international level. The threshold applied was notably low in that our jurisprudence review probed for cases that minimally connected taxation and socio-economic rights.

In that sense, finding court cases that went as far as discussing the domestic implications of a biased international tax regime to individuals' socio-economic rights was not particularly expected. After all, human rights scholarship itself has only just began exploring these intersections in more detail. But the almost complete absence of case law on the tax and human rights nexus at the international level—specifically looking at human rights boundaries and applicable principles to domestic fiscal discretion—raises one crucial question. If regional human rights courts are not developing the nexus' contours, could there be a more appropriate site for its (international) advancement?

3. Domestic litigation: is it the answer?

For good measure, it is important to acknowledge that the tax and human rights nexus could, in principle, be legally sketched by national courts with sole reference to domestic legislation. Constitutional protection of socio-economic rights is neither new nor a geographically restricted occurrence,¹⁴¹ although variations in the prevalence and justiciability of protected rights do exist across the board.¹⁴² Where such protection entails legal action, those who wish to challenge fiscal policies that violate fundamental rights could in theory initiate proceedings before a court with competence to hear cases of a constitutional character. But, without getting into unhelpful speculations over the likelihood, and extent, of procedural constraints at the national level, there are four good reasons as to why domestic litigation of the nexus is insufficient to address—and redress—inequalities between nations created by the international tax regime that curtail socio-economic rights realisation in developing countries.

First and foremost, decisions handed down by national courts that by chance impose human rights boundaries to domestic fiscal policies cannot single-handedly alter the dynamics of taxation rules that are ultimately designed at the international level. A domestic approach to the tax and human rights nexus can only be piecemeal and ad hoc at best. But, what is more, as states enter into double taxation agreements¹⁴³ (DTAs) that characteristically embody internationally defined goals, the outlines of what is purely domestic fiscal policy and what is the feasible version of domestic¹⁴⁴ become substantially hazier. Within a global market economy, domestic tax policy can be largely limited by a predetermined framework of internationally set preferences.¹⁴⁵ Governments, and those of developing countries in particular, subscribe to the international tax regime for several reasons, not in the least because they may feel compelled to do so.¹⁴⁶ In this context, constitutional review of tax policies’ substance, especially by courts of developing countries, rather than a form of virtue signalling, could be construed as defective behaviour¹⁴⁷ by participants of the regime.

This observation leads us to the second reason for domestic litigation's insufficiency to structurally change the status quo. The judicial self-restraint seen at the international level with respect to reviewing fiscal policies' substance is, to a degree, mirrored within the domestic state. Germany and the U.S. arguably represent the two extremes within a spectrum of possibilities of constitutional review of a (democratic) state's power to tax. While the German Federal Constitutional Court has actively inspected fiscal policies¹⁴⁸ against the contents of fundamental rights and constitutional principles in over a hundred cases,¹⁴⁹ the American Supreme Court has shown notable reluctance to review tax legislation on constitutional grounds.¹⁵⁰ Between these two experiences, constitutional courts around the world have been more or less inclined to go beyond procedural reviews of tax legislation. But, on the whole, domestic courts tend to refrain from fully exercising their jurisdictional powers¹⁵¹ precisely because the policy (and political) implications of such review can be far-reaching.¹⁵²

Thirdly, any ripple effect that may arise from judgements delivered by domestic courts will presumably be narrower than that likely to be kickstarted by an international court ruling. Much as judicial comity¹⁵³ is a palpable reality in the international legal order, reference to comparative constitutional law as a source of interpretation in domestic proceedings cannot be said to be a universal standard.¹⁵⁴ One notable exception to such critique is perhaps that of climate public interest litigation where constitutional courts have, on occasion, been inspired by rulings handed down by foreign peers.¹⁵⁵ But in stark opposition to what is witnessed in the realm of climate change, taxation is still widely understood as a predominantly, if not entirely, domestic affair well demarcated by the boundaries of territorial sovereignty. This is, as already noted, not an accurate depiction of reality. It could well be that topics of an indisputable transboundary nature elicit some good will in domestic judges to keenly observe what others do elsewhere. If that is the case, as long as fiscal policies are seen as the product of immaculate domestic sovereignty that is wholly legitimised by the democratic process, it seems unlikely that constitutional courts would want to draw any comparisons with judgements delivered by foreign courts.

Last but not least, it is of utmost importance to bear in mind that international taxation is, at its core, about sharing ‘in the gains from economic globalization’.¹⁵⁶ The need for an international regime that coordinates the distribution of the spoils of economic integration and growth is, therefore, not disputed. Accordingly, conceiving ways to litigate the tax and human rights nexus should not be about fostering disconcerted action by states through their domestic courts. It should be, instead, about the recognition that biased transnational economic relations disproportionately affect the realisation of socio-economic rights in some corners of the world, and yet no corresponding means of (transnational) legal redress are readily available. If distributive decisions about taxation can be made at the international level, it is only reasonable—not to say fair—that these decisions' consequences are liable to disputation at that same level.¹⁵⁷

4. International tax dispute resolution mechanisms and their (im)possibilities: identifying the blind spot in court governance

Having settled the importance of litigation of the nexus at the international level¹⁵⁸ and following a lex specialis logic, the next best site for dispute should be, in principle, one hosted by the international tax regime. That is, if international human rights frameworks do not easily accommodate fiscal-policy-related claims, it is somewhat logical to investigate whether the international tax regime contemplates channels through which human rights grievances can be brought forward. While the negative answer that invariably stems from such probe may not come as a surprise to tax experts, it aids in laying bare one of the regime's greatest deficiencies. Despite its very tangible consequences to countries' tax bases—and, therefore, to those who rely on those tax bases for the realisation of their socio-economic rights—the regime strikingly lacks an adjudication body.¹⁵⁹

More fundamentally, even widespread acceptance of the existence¹⁶⁰ and evolution¹⁶¹ of an international tax regime is a relatively recent phenomenon.¹⁶² Since the Organisation for Economic Co-operation and Development (OECD) launched the Base Erosion Profit Shifting (BEPS) Project in 2012, however, arguments questioning the regime's actuality seem to have been rendered partially moot. The creation of the so-called Inclusive Framework,¹⁶³ in particular, lends substantial credibility to the thesis that an international tax regime does, in fact, exist. That notwithstanding, its precise features are yet to be universally agreed on.¹⁶⁴ An entrenched reluctance to acknowledge the regime as such¹⁶⁵ hints at a shared awareness between those who created it that difficult, albeit necessary, discussions about the content of rules, avenues of legitimacy and relevant institutions would inevitably flow from recognition. And, because the power to tax is conceptually so interwoven with territorial sovereignty, acquiescing to a regime would result, almost by definition, in further curtailment of the latter.¹⁶⁶

Many countries, and most notably developed ones, were in the past, and still are at present, unwilling to surrender even more of their (tax) sovereignty to a global tax authority.¹⁶⁷ Absent states' willingness to establish a court to ensure that international tax conflicts get solved, it became imperative to devise other dispute resolution mechanisms (DRMs) in lieu of a court-like structure. The Mutual Agreement Procedure (MAP) has been the regime's golden standard of dispute resolution since the OECD Draft Model Tax Convention of 1963.¹⁶⁸ The Procedure was included in Article 25 of the Draft where it remained in all subsequent Model Conventions, starting with the first OECD Model Tax Convention of 1977.¹⁶⁹ In its traditional format, the MAP was designed to be a procedure spurred by a taxpayer whereby two tax authorities engage in continuous dialogue to ascertain whether double taxation of income has occurred in a given case—and, if so, which tax claim will be renounced by whom.

From this concise definition it is possible to conclude that the regime's DRM par excellence severely constrains what can or cannot be the object of legal action in matters of international taxation. The MAP aims at providing a solution to disputes that arise within the bounds of a DTA in force between involved states. An actionable controversy is therefore limited to the extent of disagreement between tax authorities on the interpretation of the contents of a signed DTA. Consequently, the MAP is not meant to be a means of challenging foundational concepts of the international tax regime, such as the very existence of DTAs in their standing format and overall ethos. By contrast, full recognition of the links ensconced in the tax and human rights nexus requires an actual paradigm shift in the way international taxation rules are thought of and designed.

Post-BEPS the MAP witnessed a few changes and is expected to be joined by other modes of dispute resolution (and prevention). While not radically altered, it is now accompanied by peer-review rounds and a correlative obligation of statistics reporting on the part of Member States of the Inclusive Framework.¹⁷⁰ It is also anticipated that traditional bilateral MAPs will slowly make room for multilateral mechanisms¹⁷¹ and for modes of dispute prevention, such as Review and Determination panels¹⁷² and Advance Price Agreements.¹⁷³ On the other hand, the mechanism for resolution of controversies arising from the implementation of the so-called Pillar Two GloBE Rules is yet to be developed.¹⁷⁴ A great amount of uncertainty still surrounds the birth and implementation of these new mechanisms. But, altogether, they suffer from the same distinctive ailments of the MAP that render it ineffective for litigation of the tax and human rights nexus.

None of these new mechanisms are vessels for reconsideration of normative preferences of the past which sustain, to date, inter-state imbalances produced by the international tax regime. Neither were they envisioned to equip anyone other than the cross-border trading corporation with the tools to push back on the regime's rules. The rationale that underpins them was, indeed, overtly conceived from the standpoint of the corporate taxpayer¹⁷⁵ (although individuals may also resort to a MAP). These mechanisms are, above all, remedies to provide relief from double taxation. They are not, by exclusion, inter-state procedures of public international law that allow for the revision of taxing rights' allocation, for example. Nor are they a form of actio popularis that enables legal accountability of domestic tax systems at the international level.

5. International tax law: a transnational mosaic

Fundamentally, these obstacles—ie, the lack of a (permanent) adjudication body and the inadequacy of available mechanisms, particularly the MAP, to challenge the regime's foundational rules—are problematic for precisely the same reason. Within the international tax regime, norm production and implementation are disjointed from foreseen mechanisms of checks and balances—a critique that admittedly holds true for global governance at large.¹⁷⁶ The regime relies, simultaneously, on a centralised model of production of norms—ie, the OECD, through its Secretariat¹⁷⁷—and a diffuse or pulverised model of dispute resolution—ie, MAP, arbitration and similar post-BEPS mechanisms—that limits legal challenges to the narrow scope of DTAs already in force. The lack of a permanent adjudication body empowered to hear cases that go beyond disagreements over the interpretation of signed DTAs culminates in a mismatch between the legal effects of internationally produced norms and remedies available to dispute them.¹⁷⁸

This incongruity can perhaps be best understood as a disruption of the traditional quadripartite classification international/domestic/public/private law from which basic considerations of democratic accountability,¹⁷⁹ jurisdiction¹⁸⁰ and legal standing¹⁸¹ depart. Insofar as (national) government officials bilaterally negotiate some aspects of DTAs within the framework of an internationally designed Model Tax Convention, these agreements are, to a degree, expressions of both international and domestic law. Then, DTAs' legal object—that is, inter-state commitments over the taxation of different categories of income generated by private actors of a pronounced transnational character—further reflects intricate aspects of public and private law. In the transnational legal mosaic that effectively emerges from such disruption, international tax bureaucrats enjoy a markedly privileged position in terms of power constraints. Indeed, the need to secure political consensus between equals is arguably the only true restriction at play.

Without a specialised body with a full grasp of the many facets of international taxation and its relationship to socio-economic rights realisation, a troublesome lacuna, or blind spot, in international court governance becomes salient. No single argument can compellingly be made that either regional human rights courts, or dispute resolution mechanisms available within the international tax regime are perfectly fit for litigation of the tax and human rights nexus. This, of course, begets the question: besides relying on strong civic mobilisation for closer constitutional scrutiny of DTAs, how can those affected by the status quo challenge the embedded rules of the international tax regime? Can novel approaches to transnational (public) litigation¹⁸² be conceived to help in achieving full recognition of the nexus at the international level?¹⁸³ Still sorely open, these interrogations should undoubtedly guide further research on the topic if we are to witness a genuine reconciliation between human rights and international taxation.

6. Conclusion

This article sought to contribute to a growing body of work that examines the sophisticated links and yet-to-be addressed gaps between international taxation and human rights. Through a systematic review of regional human rights legal instruments and respective courts' jurisprudence we conclude that, far from being a reality in practice, the tax and human rights nexus seems to be very much a doctrinal construct still. Moreover, the limited role that domestic courts can play in single-handedly altering the dynamics of tax law-making at the international level would perhaps suggest that international human rights courts should take a more active stance in future cases dealing with the topic. In fact, given that domestic courts have a markedly limited reach in that regard, and that there are, at present, no routes for (human rights) redress within the international tax regime, an important final reflection is warranted. If international tax law is, in reality, a transnational mosaic of actors and norms that is not accounted for, or captured by current regional human rights frameworks, should we be considering amending the latter or conceiving new structures of human rights governance altogether?

Acknowledgements

Special thanks are due to the participants and organisers of two events where an earlier draft of this work was presented: the workshop ‘Redefining Global Governance: A tax, trade and investment perspective in the EU and beyond’ hosted by the University of Leiden and the Netherlands Network for Human Rights Research (NNHRR) 2023 Toogdag (‘Looking to the Future: New (Human) Rights’) hosted by the University of Groningen. Their valuable comments and peer support is immensely appreciated. I further owe many thanks to the anonymous reviewer and TLT Editorial Team for the insightful feedback provided.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie [grant number 956909] (ADAPTED).

Notes

1 As can be gleaned from tax literature that scrutinises the normative foundations of taxation. See: Peter Hongler, Justice in International Tax Law: A Normative Review of the International Tax Regime (IBFD 2019); Sagit Leviner, ‘The Normative Underpinnings of Taxation’ (2012) 13 Nevada Law Journal ; Nancy H. Kaufman, ‘Fairness and the Taxation of International Income’ (1998) 29 Law and Policy in International Business 145.

2 Johanna Stark, ‘Tax Justice Beyond National Borders: International or Interpersonal?’ (2022) 42 Oxford Journal of Legal Studies 133; Ivan Ozai, ‘Two Accounts of International Tax Justice’ (2020) 33 Canadian Journal of Law & Jurisprudence 317; Thomas Rixen, ‘Tax Competition and Inequality: The Case for Global Tax Governance’ (2011) 17 Global Governance 447.

3 Nikki Reisch, ‘Taxation and Human Rights: Mapping the Landscape’ in Philip G. Alston and Nikki R. Reisch (eds), Tax, Inequality, and Human Rights (Oxford University Press 2019) 113; Ignacio Saiz, ‘Resourcing Rights: Combating Tax Injustice from a Human Rights Perspective’ in Aoife Nolan, Rory O’Connell and Colin Harvey (eds), Human Rights and Public Finance: Budgets and the Promotion of Economic and Social Rights (Hart Publishing 2013); Attiya Waris, Tax and Development: Solving Kenya's Fiscal Crisis through Human Rights (LawAfrica 2013).

4 Salome Chigubu and Thabo Legwaila, ‘Converging Tax Policy and Human Rights in the Face of Tax Abuse: A Developing Country Perspective’ (2021) 11 Constitutional Court Review; Annet Wanyana Oguttu and Monica Iyer, ‘Tax Abuse and Implications for Human Rights in Africa’ in Philip G. Alston and Nikki R. Reisch (eds), Tax, Inequality, and Human Rights (Oxford University Press 2019).

5 Olivier De Schutter, Nicholas J. Lusiani and Sergio Chaparro, 'Re-Righting the International Tax Rules: Operationalising Human Rights in the Struggle to Tax Multinational Companies’ (2020) 24 The International Journal of Human Rights 1370.

6 Irene Burgers and Irma Mosquera Valderrama, ‘Corporate Taxation and BEPS: A Fair Slice for Developing Countries?’ (2017) 1 Erasmus Law Review.

7 Borrowing from Nikki Reisch's broader use of the term, this article employs it ascribing a more specific meaning, similar to that of the ‘collective rights’ vision of tax and human rights broached in: Juliane Kokott and Pasquale Pistone (eds), Taxpayers in International Law: International Minimum Standards for the Protection of Taxpayers Rights (Hart Publishing, Bloomsbury Publishing Plc, 2022) 71 (‘The second definition includes “collective rights” based on the rights of citizens to have their government raise sufficient revenue from taxation and spend that revenue on improving the rights and lives of the population generally. (…) These are generally positive “rights”, requiring governments to take certain steps in relation to taxation (and to refrain from certain steps).’)

8 Afton Titus and Tracy Gutuza, ‘The Relationship Between Tax & Incentives and Human Rights Obligations in the Drive to Attract Foreign Direct Investment: Are Developing Countries in Africa Getting It Right?’ in Tracy Gutuza and Debbie Collier (eds), Foreign Direct Investment and the Law: Perspectives from Selected African Countries (Juta 2019); Radhika Balakrishnan, James Heintz and Diane Elson, Rethinking Economic Policy for Social Justice: The Radical Potential of Human Rights (Economics as Social Theory, Routledge, 2016).

9 Joe Wills and Ben TC Warwick, ‘Contesting Austerity: The Potential and Pitfalls of Socioeconomic Rights Discourse’ (2016) 23 Indiana Journal of Global Legal Studies 629.

10 Here understood within the meaning routinely attributed in scholarship to the concept of transnational law. That is, all law that regulates cross-border relationships, surpassing the dichotomy domestic/international law, and that does not fit neatly into the standard black boxes of public and private international law. See, generally: Peer Zumbansen, ‘Transnational Law: Theories and Applications’ in Peer Zumbansen (ed), The Oxford Handbook of Transnational Law (Oxford University Press, Oxford 2021); Kaarlo Tuori, ‘Transnational Law: On Legal Hybrids and Perspectivism’ in Miguel Maduro, Kaarlo Tuori and Suvi Sankari (eds), Transnational Law: Rethinking European Law and Legal Thinking (Cambridge University Press, Cambridge 2014). Transnational fiscal relations would then be those established between public and private actors with varying effects to state and non-state actors.

11 Olivier De Schutter, The Rights-Based Welfare State: Public Budgets and Economic and Social Rights (Friedrich-Ebert Stiftung 2018).

12 A similar point was made by Anne Peters in relation to the link between corruption and human rights in: Anne Peters, ‘Corruption as a Violation of International Human Rights’ (2018) 29 The European Journal of International Law.

13 Olivier De Schutter, ‘Taxing for the Realization of Economic Social and Cultural Rights’ in Nikki R. Reisch and Philip G. Alston (eds), Tax, Inequality, and Human Rights (Oxford University Press 2019).

14 See, eg, UN Committee on Economic Social and Cultural Rights, ‘Concluding observations on the sixth periodic report of the United Kingdom of Great Britain and Northern Ireland’ (2016) E/C.12/GBR/CO/6; UN Committee on the Elimination of Discrimination against Women, ‘Concluding observations on the combined fourth and fifth periodic reports of Switzerland’ (2016) CEDAW/C/CHE/CO/4-5.

15 Wolfgang Schön, ‘Taxation and Democracy’ (2019) 72 Tax Law Review 235, 243.

16 Illustrated, for example, by the withdrawal and subsequent return of the U.S., the second largest carbon dioxide emitter in the world, to the framework of the Paris Agreement.

17 Jannika Jahn, ‘Domestic Courts as Guarantors of International Climate Cooperation: Insights from the German Constitutional Court's Climate Decision’ (2022) 21 International Journal of Comparative Law 859.

18 Some important caveats to the idea that courts can ‘save the world’ are made in: Malcom Langford, 'The impact of public interest litigation: the case of socio-economic rights’ (2021) 27 Australian Journal of Human Rights 505.

19 African Union, African (Banjul) Charter of Humans and Peoples’ Rights (1981).

20 African Union, Protocol to the African Charter on Human and Peoples’ Rights on the Establishment of an African Court on Human and Peoples’ Rights (2003).

21 Including on behalf of a citizen whose human rights have been violated by another State Party

22 Articles 5(3) and 34(6) of the Protocol (n 20).

23 Tetevi Davi and Ezéchiel Amani, ‘Another One Bites the Dust: Côte d’Ivoire to End Individual and NGO Access to the African Court’ (EJIL: Talk!, 2020) <https://www.ejiltalk.org/another-one-bites-the-dust-cote-divoire-to-end-individual-and-ngo-access-to-the-african-court/> accessed 8 February 2023.

24 African Union, African (Banjul) Charter of Humans and Peoples’ Rights.

25 According to information retrieved from the African Court's case law website, from 1 January 2020 until 31 March 2024, 82 judgements (on merits, merits and reparations, and interpretation) were handed down: 4 in 2024, 30 in 2023, 17 in 2022, 18 in 2021, and 13 in 2020. None of them contemplated any taxation or fiscal-state related issues. The same held true for previous decisions. See: African Court on Human and Peoples’ Rights, 'African Court Law Report: Volume 4 (2020)' (2022) ; African Court on Human and Peoples’ Rights, 'African Court Law Reports: Volume 3 (2019)' (2021) ; African Court on Human and Peoples’ Rights, 'African Court Law Report: Volume 2 (2017–2018)' (2019) ; African Court on Human and Peoples’ Rights, 'African Court Law Report: Volume 1 (2006–2016)' (2017).

26 The Request for Advisory Opinion made by NGO SERAP arguably presented the best opportunity yet to obtain some clarification on aspects relevant to the tax and human rights nexus; namely whether extreme, systemic and widespread poverty violates human rights protected by the Banjul Charter. However, the Court found it lacked personal jurisdiction to analyse the matter. See: Request for Advisory Opinion by the Socio-Economic Rights and Accountability Project (SERAP), No. 001/2013, African Court of Human and Peoples’ Rights, 26 May 2017.

27 African Union, African (Banjul) Charter of Humans and Peoples’ Rights.

28 Ibid.

29 African Commission on Human and Peoples’ Rights v. Republic of Kenya (merits), no. 006/2012, ACtHPR, 26 May 2017.

30 Drawing inspiration from the Inter-American Court of Human Rights’ jurisprudence.

31 African Commission on Human and Peoples’ Rights v. Republic of Kenya (reparations), no. 006/2012, § 155, ACtHPR, 23 June 2022.

32 Karen J Alter, Laurence R Helfer and Jacqueline R McAllister, ‘A New International Human Rights Court for West Africa: The ECOWAS Community Court of Justice’ (2013) 107 The American Journal of International Law 737.

33 The ECOWAS Court's competence was originally limited to matters related to economic integration. That changed with the adoption of a Supplementary Protocol in 2005. According to Article 9(4) of the 1991 Protocol on the Community Court of Justice (as amended in 2005 by Supplementary Protocol A/SP.1/01/05), the ECOWAS Court has jurisdiction ‘to determine case of violation of human rights that occur in any Member State’. See: Economic Community of West African States (ECOWAS), Protocol A/P.l/7/91 on the Community Court of Justice (1991).

34 The National Co-ordinating Group of Departmental Representatives of the Cocoa-Coffee Sector (CNDD) v. Republic of Côte D’Ivoire, ECW/CCJ/JUD/05/09, § 41, ECOWASCJ, 17 December 2009.

35 Ibid § 61.

36 Ibid § 42.

37 Ibid § 43.

38 Ibid § 56.

39 Ibid § 59.

40 Marie-Pierre Granger and Orsolya Salát, ‘Framing Justice Claims as Legal Rights: How Law (mis-)handles Injustices’ in Trudie Knijn and Dorota Lepianka (eds), Justice and Vulnerability in Europe An Interdisciplinary Approach (Edward Elgar Publishing 2020).

41 See, eg, Sébastien Jodoin, Shannon Snow and Arielle Corobow, ‘Realizing the Right to Be Cold? Framing Processes and Outcomes Associated with the Inuit Petition on Human Rights and Global Warming’ (2020) 54 Law & Society Review 168 (on framing a climate justice related claim as a legal (human rights) entitlement).

42 While the ECOWAS Court can, in principle, use the Banjul Charter as framework of reference to deliver its judgements (Article (g) of the Revised ECOWAS Treaty) it did not do so in CNDD v Co^te d’Ivoire. In any event, the Court must be careful not to usurp the ACtHPR's competence when interpreting the Charter.

43 Colm O’Cinneide, ‘Giving Legal Substance to the Social Minimum’ in Toomas Kotkas, Ingrid Leijten and Frans Pennings (eds), Specifying and Securing a Social Minimum in the Battle Against Poverty (Hart Publishing 2019) (on the indeterminacy of socio-economic rights and the difficulties of using a legal rights discourse to outline their content/substance).

44 See, eg, Mathias Möschel, ‘Jura Novit Curia and the European Court of Human Rights’ (2022) 33 European Journal of International Law 631.

45 Something indeed done by the ACtHPR. See: Yakaré-Oulé (Nani) Jansen Reventlow and Rosa Curling, 'The Unique Jurisdiction of the African Court on Human and People's Rights: Protection of Human Rights Beyond the African Charter' (2019) 33 Emory International Law Review 219.

46 Article 34 of the ECHR.

47 Ingrid Leijten, Core Socio-Economic Rights and the European Court of Human Rights (Cambridge University Press, Cambridge 2018) 214 ('The ECtHR is a unique court. Established in 1950 to secure the collective enforcement of certain of the rights stated in the UDHR, its practice has turned into the most effective example of supranational fundamental rights protection worldwide.’).

48 Airey v. Ireland, no. 6289/73, § 26, ECHR, 9 October 1979.

49 Such as the rights to health, housing, and social security, for example. See: European Court of Human Rights, 'Guide on the case-law of the European Convention on Human Rights: Social rights’ (2022).

50 Leijten (n 47).

51 See, eg, Ezgi Yildiz, ‘A Court with Many Faces: Judicial Characters and Modes of Norm Development in the European Court of Human Rights’ (2020) 31 European Journal of International Law 73.

52 Françoise Tulkens, ‘Judicial Activism v Judicial Restraint: Practical Experience of This (False) Dilemma at the European Court of Human Rights’ (2022) 3 European Convention on Human Rights Review 293.

53 Alexander Kornezov, ‘Social Rights, the Charter, and the ECHR: Caveats, Austerity, and Other Disasters’ in Frank Vandenbroucke, Catherine Barnard and Geert De Baere (eds), A European Social Union after the Crisis (Cambridge University Press, 2017) 429.

54 Which reads: ‘Every natural or legal person is entitled to the peaceful enjoyment of his possessions. No one shall be deprived of his possessions except in the public interest and subject to the conditions provided for by law and by the general principles of international law. The preceding provisions shall not, however, in any way impair the right of a State to enforce such laws as it deems necessary to control the use of property in accordance with the general interest or to secure the payment of taxes or other contributions or penalties.’

55 The first case in which the ECtHR was asked to provide guidance on the contents of Article 1 of Protocol 1 concerned the seizing and destruction of copies of a schoolbook considered obscene by British authorities under national law. See: Handyside v. The United Kingdom, no. 5493/72, ECHR, 7 December 1996.

56 Kopecký v. Slovakia no. 44912/98, §§ 45-51, ECHR, 28 September 2004.

57 For an overview of the Council of Europe case law (and more broadly) on taxpayers’ property rights, see: Kokott and Pistone (eds), Taxpayers in International Law: International Minimum Standards for the Protection of Taxpayers Rights.

58 Generally, see: Rusen Ergec, ‘Taxation and Property Rights under the European Convention on Human Rights’ (2011) 39 INTERTAX 2.

59 Reuven S. Avi-Yonah and Gianluca Mazzoni, ‘Taxation and Human Rights: A Delicate Balance’ in Philip G. Alston and Nikki R. Reisch (eds), Tax, Inequality, and Human Rights (Oxford University Press 2019) 260–62.

60 Oao Neftyanaya Kompaniya Yukos v. Russia, no. 14902/04, §§ 608-16, ECHR, 20 September 2011.

61 Ingrid Leijten, ‘The Right to Minimum Subsistence and Property Protection under the ECHR: Never the Twain Shall Meet?’ (2019) 21 European Journal of Social Security 307.

62 At the time of drafting, a search on the HUDOC database yields 12,467 results for cases connected to Article 1 of Protocol 1. When a search filter is added so that results specifically relate to paragraph 2 of the provision (which mentions taxes) the yield drops to 1034 results.

63 Béláné Nagy v. Hungary, no. 53080/13, § 72, ECHR, 13 December 2016.

64 For example, that it is not confiscatory in nature. See: R.Sz. v. Hungary, no. 41838/11, § 31, ECHR, 2 July 2013.

65 Leijten (n 61).

66 Correia de Matos v. Portugal, no. 56402/12, § 8, ECHR, 4 April 2018 (dissenting opinion of Judge Pinto de Albuquerque joined by Judge Sajó).

67 N.K.M. v. Hungary, no. 66529/11, §§ 49-50, ECHR, 14 May 2013.

68 Stec and Others v. The United Kingdom, nos. 65731/01 and 65900/01, § 52, ECHR, 12 April 2006.

69 Burden v. The United Kingdom, no. 13378/05, § 59, ECHR, 29 April 2008; R.Sz. v. Hungary; Gáll v. Hungary, no. 49570/11, § 49, ECHR, 25 June 2013; N.K.M. v. Hungary.

70 Valverde Digon v. Spain, no. 22386/19, § 50, ECHR, 26 January 2023.

71 Ibid.

72 Da Silva Carvalho Rico v. Portugal (dec.), no. 13341/14, § 31, ECHR, 1 September 2015.

73 Da Conceição Mateus and Santos Januário v. Portugal (dec.), nos. 62235/12 and 57725/12, § 22, ECHR, 8 October 2013.

74 James and Others v. The United Kingdom, no. 8793/79, § 67, ECHR, 21 February 1986.

75 Thomas von Danwitz, 'The Rule of Law in the Recent Jurisprudence of the ECJ' (2014) 37 Fordham International Law Journal 1311, 1314 (on the principles that, combined, embody the rule of law, according to the European Court of Justice's jurisprudence).

76 Béláné Nagy v. Hungary.

77 Ibid § 113.

78 Fábián v. Hungary, no. 78117/13, § 114, ECHR, 5 September 2017.

79 Baczúr v. Hungary, no. 8263/15, §§ 28–29, ECHR, 7 March 2017.

80 N.K.M. v. Hungary.

81 Baczúr v. Hungary.

82 Fábián v. Hungary.

83 N.K.M. v. Hungary.

84 Kornezov, ‘Social Rights, the Charter, and the ECHR: Caveats, Austerity, and Other Disasters’.

85 For all see: Koufaki and Adedy v. Greece (dec.), nos. 57665/12 and 57657/12, ECHR, 7 May 2013.

86 Savickis and Others v. Latvia, no. 49270/11, 102-03, ECHR, 9 June 2022.

87 At the Béláné Nagy v. Hungary hearing, for instance, the Hungarian government was found to have acted in violation of the ECHR even after having ‘cautioned against the stealthy creation of an independent European social law on an undefined basis, without the checks and balances that only a State legislature could guarantee.’ See: Béláné Nagy v. Hungary.

88 Andreas Hofmann, 'The legal mobilisation of EU market freedoms: strategic action or random noise?' (2024) West European Politics 1 (emphasising that so-called ‘one-shot litigants’, ie, self-interest litigants that do not strategically set out to effect policy change through litigation, may also contribute to European Union Law mobilisation).

89 A difficulty already evidenced in climate litigation. See: Helen Arling and Hani Taghavi, 'KlimaSeniorinnen v. Switzerland – A New Era for Climate Change Protection or Proceeding with the Status Quo?' (EJIL: Talk!, 2023) <https://www.ejiltalk.org/klimaseniorinnen-v-switzerland-a-new-era-for-climate-change-protection-or-proceeding-with-the-status-quo/> accessed 18 September 2023.

90 Savickis and Others v. Latvia.

91 Ibid § 97.

92 TRS Allan, ‘Human Rights and Judicial Review: A Critique of “Due Deference”’ (2006) 65 The Cambridge Law Journal 671, 694.

93 Eyal Benvenisti, 'The Margin of Appreciation, Subsidiarity and Global Challenges to Democracy' (2018) 9 Journal of International Dispute Settlement 240, 245; Balakrishnan, Heintz and Elson (n 8).

94 Tsilly Dagan, ‘Klaus Vogel Lecture 2021: Unbundled Tax Sovereignty – Refining the Challenges’ (2022) 76 Bulletin for International Taxation 321.

95 Cristina Fasone, ‘The Constitutional Role of Independent Fiscal Institutions in the Eurozone’ (2022) 23 German Law Journal 257, 265 (‘Across the EU Member States parliaments have been frequently marginalized in fiscal decision-making and are less equipped with information on fiscal policy compared to the governments.’).

96 Tsilly Dagan, ‘International Tax and Global Justice’' (2017) 18 Theoretical Inquiries in Law 90.

97 Eyal Benvenisti, ‘Community Interests in International Adjudication’ in Eyal Benvenisti and Georg Nolte (eds), Community Interests Across International Law (Oxford University Press 2018) 83 (‘Because regional and international courts are in a position to rebalance power-relations and to promote global welfare through adjudication, they have a responsibility, if not an outright moral duty, to do so, and to develop international law accordingly.’).

98 Lorand Bartels, ‘The EU's Human Rights Obligations in Relation to Policies with Extraterritorial Effects’ (2014) 25 The European Journal of International Law 1077.

99 N.D. and N.T. v. Spain, nos. 8675/15 and 8697/15, 102-04, ECHR, 13 February 2020 (concurring opinion of Judge Pejchal) (bold emphasis added).

100 Organization of the American States (OAS), Charter of the Organisation of American States (1948).

101 Following the amendments to the OAS Charter introduced by the Protocol of Buenos Aires. See: Thomas Buergenthal, ‘The Revised OAS Charter and the Protection of Human Rights’ (1975) 69 The American Journal of International Law 828.

102 Organization of American States (OAS), American Convention on Human Rights, ‘Pact of San Jose, Costa Rica’ (1969).

103 Either by individuals or nongovernmental entities, as provided for by Article 44 of the ACHR.

104 (OAS), American Convention on Human Rights, ‘Pact of San Jose, Costa Rica’, Articles 41 to 51.

105 Ibid, Article 61.

106 As recognised in Cuscul Pivaral et al. v. Guatemala (Preliminary objection, merits, reparations and costs), Series C No. 359, § 88, IACtHR, 23 August 2018.

107 Although Article 8(1) of the ACHR stipulates that a right to a fair trial, and connected guarantees of due process, exists (also) in procedures of a fiscal nature. Such specificity is rather interesting when contrasted with the ‘judge-made’ procedural rights guarantee found in the ECtHR's case law.

108 OAS, Charter of the Organisation of American States, Article 34.

109 Sara Parolari, ‘From a Formal to a Substantial Approach: Sources of Law and Fiscal Federalism’ in Alice Valdesalici and Francesco Palermo (eds), Comparing Fiscal Federalism (Studies in Territorial and Cultural Diversity Governance, Brill, Nijhoff 2018) 23–8.

110 Alice Valdesalici, ‘Defining Fiscal Federalism’ in Alice Valdesalici and Francesco Palermo (eds), Comparing Fiscal Federalism (Studies in Territorial and Cultural Diversity Governance, Brill, Nijhoff 2018) 18.

111 With respect to case law on Article 29(6) of the Banjul Charter.

112 Miskito divers (Lemoth Morris et al.) v. Honduras, Series C No. 432, §§ 68–69, IACtHR, 31 August 2021.

113 Indigenous Communities of the Lhaka Honhat (Our Land) Association v. Argentina (Merits, reparations and costs), Series C No. 400, § 216, IACtHR, 6 February 2020.

114 Which is a good a temporal parameter to gauge the speed at which the IACtHR has evolved its jurisprudence in this respect.

115 Lagos del Campo v. Peru (Preliminary objections, merits, reparations and costs), Series C 340, § 154, IACtHR, 31 August 2017.

116 Juan Pablo Rodríguez, ‘The politics of neoliberalism in Latin America: dynamics of resilience and contestation’ (2021) 15 Sociology Compass e12845.

117 René Urueña, ‘Double or Nothing: The Inter-American Court of Human Rights in an Increasingly Adverse Context’ (2018) 35 Wisconsin International Law Journal 398, 414.

118 Ibid.

119 Pablo Contreras, ‘National Discretion and International Deference in the Restriction of Human Rights: A Comparison Between the Jurisprudence of the European and the Inter-American Court of Human Rights’ (2012) 11 Northwestern Journal of International Human Rights 28.

120 Laurence Burgorgue-Larsen, ‘Conventionality Control: Inter-American Court of Human Rights (IACtHR)’, Max Planck Encyclopedia of Procedural International Law (2018) (clarifying that, according to the doctrine, there is an international obligation on public authorities in state parties to the ACHR to interpret domestic legal norms in a manner compatible with the ACHR).

121 Assuming it works as intended, the downside to this model is the expected lack of uniformity in the interpretation of the ACHR. See: Sergio García Ramírez, ‘The Relationship between Inter-American Jurisdiction and States (National Systems): Some Pertinent Questions’ (2015) 5 Notre Dame Journal of International & Comparative Law 115, 140.

122 Ariel E. Dulitzy, ‘An Inter-American Constitutional Court? The Invention of the Conventionality Control by the Inter-American Court of Human Rights’ (2015) 50 Texas International Law Journal 45, 74.

123 Françoise Hampson, Claudia Martin and Frans Viljoen, 'Comparing Access to Regional Human Rights Courts and Commissions in Europe, the Americas, and Africa’ (2018) 16 International Journal of Constitutional Law 161.

124 Inter-American Commission on Human Rights, 'Digest of the Inter-American Commission on Human Rights on its Admissibility and Competence Criteria' (2020) OEA/Ser.L/V/II.175, 19.

125 Muelle Flores v. Peru (Preliminary objections, merits, reparations and costs), Series C No. 375, IACtHR, 6 March 2019.

126 Ibid § 183.

127 Ibid.

128 Ibid § 192.

129 National Association of Discharged and Retired Employees of the National Tax Administration Superintendence (ANCEJUB-SUNAT) v. Peru (Preliminary objections, merits, reparations and costs), Series C No. 394, IACtHR, 21 November 2019.

130 Ibid § 159.

131 Ibid.

132 Balakrishnan, Heintz and Elson (n 8).

133 Cuscul Pivaral et al. v. Guatemala (Preliminary objection, merits, reparations and costs).

134 Ibid § 220.

135 An idea incorporated by the ACtHPR as already mentioned (n 25).

136 Cuscul Pivaral et al. v. Guatemala (Preliminary objection, merits, reparations and costs) (partially dissenting opinion Judge Humberto Antonio Sierra Porto).

137 Guevara Díaz v. Costa Rica (Merits, reparations and costs), Series C No. 453, § 50, IACtHR, 22 June 2022 (concurring opinion Judge Rodrigo Mudrovitsch).

138 OAS, Charter of the Organisation of American States.

139 As was the case with the minimum core of socio-economic protection developed by the ECHR.

140 Avi-Yonah S. Reuven and Yoseph M. Edrey, ‘Constitutional Review of Federal Tax Legislation’ (2023) University of Illinois Tax Review 3, 17. (‘Yet it is quite difficult for the government to provide solid legal evidence that it provides full consideration to each and every member of society. Accordingly, we need an assumption that the consideration is provided by the government. The burden of proof on consent is shifted to the taxpayers. If a taxpayer, or a group of tax-payers, argue that they did not receive a quid pro quo for their tax payments and therefore did not consent to pay the tax, they bear a very heavy burden.’).

141 Analyses of the constitutionalisation of socio-economic rights in Africa, Latin-America and Europe abound in the literature. In the European case, scholarship widely focuses on socio-economic rights’ protection at the EU level. See, generally.: John Cantius Mubangizi, ‘The Constitutional Protection of Socio-Economic Rights in Selected African Countries: A Comparative Evaluation’ (2006) 2 The African Journal of Legal Studies 1 ; Rodrigo Uprimny, 'The Recent Transformation of Constitutional Law in Latin America: Trends and Challenges’ (2011) 89 Texas Law Review 1587; Orsola Razzolini, ‘Constitutionalization of Socio-Economic Rights at the EU Level: Some Critical Notes’ (2015) 98 Kritische Vierteljahresschrift für Gesetzgebung und Rechtswissenschaft 284; Bruno de Witte, ‘Two Charters and a Pillar: The Slow Constitutionalization of Social Rights in European Law’ in Uladzislau Belavusau and Aleksandra Gliszczynska-Grabias (eds), Constitutionalism under Stress (Oxford University Press 2020).

142 Courtney Jung, Ran Hirschl and Evan Rosevear, ‘Economic and Social Rights in National Constitutions’ (2014) 62 The American Journal of Comparative Law 1043.

143 The global network of over 3,000 DTAs currently in force is usually seen as the departing point of positive international tax law.

144 Reuven S. Avi-Yonah, 'Commentary (Response to article by H. David Rosenbloom)' (2000) 53 Tax Law Review 167, 169–70. ('Suppose you were advising a developing country or transition economy that wanted to adopt an income tax for the first time. How free do you think you would be to write the international tax rules for such a country in any way you wanted, assuming that it wished to attract foreign investment? I would argue that the freedom of most countries to adopt international tax rules is severely constrained, even before entering into any tax treaties, by the need to adapt to generally accepted principles of international taxation. Even if divergent rules have been adopted, the process of integration into the world economy forces change.’).

145 Laurens van Apeldoorn, ‘International Taxation and the Erosion of Sovereignty’ in Peter Dietsch and Thomas Rixen (eds), Global Tax Governance: What is Wrong with It and How to Fix It (ECPR Press, Colchester 2016) (on the reduction of tax sovereignty due to states’ fiscal interdependence).

146 Martin Hearson, ‘When Do Developing Countries Negotiate Away Their Corporate Tax Base?’ (2018) 30 Journal of International Development 233.

147 Within international relations’ literature, defection is often defined as non-cooperation or refusal to join in on an established norm or regime. See: Allison Christians, ‘How Nations Share’ (2012) 87 Indiana Law Journal 1407, 1448–49 (on the balance between costs and legitimacy of defecting from the established international tax regime).

148 Oliver Lepsius, ‘Constitutional Review of Tax Laws and the Unconstitutionality of the German Inheritance Tax’ (2015) 16 German Law Journal 1191, 1219.

149 Joachim Englisch and Hanno Kube, ‘Constitutional Requirements for Substantive Tax Law in Federal Republic of Germany’ (2023) 2 Review of International and European Economic Law.

150 Reuven and Edrey (n 140).

151 On varying degrees of judicial deference to the Legislature or the Executive demonstrated by constitutional courts in different countries, see eg, Hans Gribnau and Sonja Dusarduijn, 'Constitutional Taxation in the Netherlands’ (2023) 3 Review of International & European Economic Law 169; Olivia Minatta, María Emilia Mamberti and Sergio Chaparro, 'Constitutional Principles of Public Finance Law and Comparative Jurisprudence’ (2021); Jarosław Kantorowicz, ‘Judges as Fiscal Activits: Can Constitutional Review Shape Public Finance?’ (2014) 5 DANUBE: Law and Economics Review 79.

152 Although Anne Peters submits that fragmentation in international law has led to a useful politicisation of international legal processes. See: Anne Peters, ‘The refinement of international law: From fragmentation to regime interaction and politicization’ (2017) 15 ICON 671.

153 Broadly understood as the mutual respect shown by domestic courts when legal orders intersect each other. It has been argued that such reverence also fulfils a regulatory function. See: Elisa D’Alterio, ‘From Judicial Comity to Legal Comity: A Judicial Solution to Global Disorder?’ (2011) 9 International Journal of Constitutional Law 394.

154 Ran Hirschl, Comparative Matters: The Renaissance of Comparative Constitutional Law (Oxford University Press 2014) 214/15. Although some scholars argue exactly the opposite. See: Michael Da Silva, ‘International “Constitutions” and Comparative Constitutional Law’ (2020) 10 Notre Dame Journal of International & Comparative Law 139.

155 The decision delivered by the Dutch Supreme Court on the much publicised Urgenda case has had a remarkable knock-on effect on other courts of similar constitutional stature. See: Emily Barritt, ‘Consciously Transnational: Urgenda and the Shape of Climate Change Litigation: The State of the Netherlands (Ministry of Economic Affairs and Climate Policy) v Urgenda Foundation’ (2020) 22 Environmental Law Review 296.

156 Christians (n 147) 1412.

157 This argument is theoretically grounded on Nancy Fraser's notions of ‘meta-political injustice’ and ‘misframing’. In a nutshell, Fraser's account of circumstances of abnormal justice posits that political spaces of transnational power are created at the expense of the global poor who are then excluded from consideration in matters of representation, distribution and political recognition. See: Nancy Fraser, ‘Who Counts? Dilemmas of Justice in a Postwestphalian World’ (2009) 41 Antipode 281, 286.

158 Or at least litigation whose effects may contribute to changes at the international level.

159 Julien Chaisse and Irma Mosquera Valderrama, ‘Public International Law, International Taxation and Tax Dispute Resolution’ (2022) Asia Pacific Law Review 192; Arthur J. Cockfield, ‘Shaping International Tax Law and Policy in Challenging Times’ (2018) 54 Stanford Journal of International Law 233.

160 Michael P. Devereux and others, Taxing Profit in a Global Economy (Oxford University Press 2021) 85.

161 Reuven Avi-Yonah, ‘International Taxation, Globalization, and the Economic Digital Divide’ (2023) 26 Journal of International Economic Law 101.

162 Just over fifteen years ago, tax scholarship was debating whether one could really speak of such a thing. See: Reuven S. Avi-Yonah, International Tax as International Law: An Analysis of the International Tax Regime (Cambridge Tax Law Series, Cambridge University Press 2007).

163 See, generally: Chris Noonan and Victoria Plekhanova, ‘Compliance Challenges of the BEPS Two-Pillar Solution’ (2022) British Tax Review 512; Allison Christians and Laurens van Apeldoorn, ‘The OECD Inclusive Framework’ (2018) Bulletin for International Taxation 226.

164 They are tentatively fleshed out in Devereux and others (n 160).

165 Christians (n 147) (on the role played by soft law in, among other things, obscuring power politics in international taxation).

166 As compared to the portion of sovereignty that countries already surrender through the signing of DTAs.

167 Schön (n 15) 243.

168 OECD, ‘Draft Double Taxation Convention on Income and Capital’ (1963), 16.

169 OECD, ‘Model Double Taxation Convention on Income and on Capital’ (1977), 42.

170 See BEPS Action 14.

171 OECD, ‘Manual on the Handling of Multilateral Mutual Agreement Procedures and Advance Pricing Arrangements’ (2023).

172 OECD, ‘Tax Challenges Arising from Digitalisation – Report on Pillar One Blueprint: Inclusive Framework on BEPS’ (2020) 170.

173 Ibid 190.

174 OECD, ‘Tax Challenges Arising from Digitalisation – Report on Pillar Two Blueprint: Inclusive Framework on BEPS’ (2020) 179.

175 The advice provided in the Commentary on Article 25 section of the OECD Model Tax Convention demonstrates this point rather well. See, for example, paragraphs 9-13 of the commentary where the most common cases that give rise to a MAP are listed, and specific reference to transfer pricing practices are made. In: OECD, 'Model Tax Convention on Income and on Capital: Condensed Version’ (2017), 431–33.

176 Michael Zürn, A Theory of Global Governance: Authority, Legitimacy, and Contestation (Oxford University Press, Oxford 2018) ('This inequality sometimes goes so far that the representatives of the most powerful states combine legislative (setting the rules), executive (making decisions on the basis of the rules), and administrative (implementing the decisions) competencies in the absence of judicial supervision.’).

177 Nico Krisch, ‘The Decay of Consent: International Law in an Age of Global Public Goods’ (2017) 108 The American Journal of International Law 1 (on the shift to non-consensual rulemaking at the international level).

178 Chris Thornhill, ‘Transnational Constitutional Law’ in Peer Zumbansen (ed), The Oxford Handbook of Transnational Law (Oxford University Press 2021) 149.

179 Eyal Benvenisti and George W. Downs, ‘Toward Global Checks and Balances’ (2009) 20 Constitutional Political Economy 366.

180 Nico Krisch, ‘Jurisdiction Unbound: (Extra)territorial Regulation as Global Governance’ (2022) 33 European Journal of International Law 481 (on the phenomenon of jurisdictional assemblage).

181 Nancy Fraser, Scales of Justice: Reimagining Political Space in a Globalizing World (Columbia University Press, New York 2009) 68 (‘Thus, a theory of justice for abnormal times must be dialogical. By itself, however, dialogue is not a solution. As soon as we accept that conflicts concerning the frame must be handled discursively, we need to envision a way in which public debates concerning the “who” could eventuate in binding resolutions. Absent an account of the relation between contestation and legitimate decision-making, we have no way to implement the all-subject principle, hence no way to process disputes in abnormal justice.’).

182 Harold Hongju Koht, “Transnational Public Law Litigation” (1991) 100 The Yale Law Journal 2347, 2399–400 (asking whether we could collectively let go of idealist/realist polarities in order to conceive a new model of the international legal process that embraces its complex richness).

183 Peters (n 152) (‘Some forum-shopping may legitimately serve as a “counterinsurgency strategy” of weaker actors’).