JUST: a measure of jury system trustworthiness

ABSTRACT

Three studies developed and tested a new measure of the perceived trustworthiness of the jury system, the 23-item Jury System Trustworthiness (JUST) scale, and assessed the scale’s convergent and discriminant validity. Study 1 assessed the scale’s factor structure and relation to other relevant constructs. In Studies 2 and 3, the JUST scale was administered to participants in two separate mock juror studies. The results of all three studies supported the hypothesized factor structure of the measure but showed that a simplified, 7-item measure was also effective. Overall, participants’ perceptions of juries were moderately positive, and the JUST scale was related to attitudes toward the police, authoritarianism, belief in a just world, juror bias, preference for a jury (vs. a bench) trial, and intention to respond to a jury summons. It also explained a unique portion of the variance in jury-specific beliefs and behavioral intentions, such as preference for a jury trial and response to a summons, beyond that accounted for by other legal attitudes. The JUST scale was not related to verdict decisions in either mock trial after controlling for authoritarianism. Several individual differences (e.g. age, race/ethnicity) were also related to attitudes toward the jury system.

KEYWORDS:

• Attitudes
• individual differences
• juror decision making
• legal authoritarianism
• Mock Juries

Acknowledgements

Portions of this paper were presented at the 2016 and 2018 meetings of the American Psychology-Law Society. We are grateful to Mauricio Alvarez, Christine McDermott, Clayton Peoples, Sarah Trescher, Matt West, Emily Wood, and Logan Yelderman for their assistance with Study 2, and to Bailey Barnes for assistance with Study 3. We appreciate Mary Rose’s comments on previous versions of the manuscript. We dedicate this paper to the memory of Larry Wrightsman, whose pioneering work on legal attitudes has long been a source of inspiration.

Disclosure statement

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

Notes

1 In their compilation of juror attitude measures, Wrightsman et al. (2004) included a measure of attitudes toward jury service, but they did not describe its psychometric properties, which might explain why the measure has not been widely adopted by the field.

2 The trust literature is vast, consisting of more than 100 different measures (McEvily & Tortoriello, 2011). Our previous work started with relatively long lists of items per construct, which were then whittled down to smaller sets of items that addressed the conceptual contours of the hypothesized dimensions and that performed well when subjected to psychometric evaluation (PytlikZillig et al., 2016, 2017).

3 Death qualification was significantly related to six of the seven dimensions (excluding identification; F’s > 6.60, p’s < .02), such that subscale scores where lower (i.e. more negative) for death-qualified participants. Because the relationship between death qualification and jurors’ judgments is well established (e.g. Yelderman et al., 2016), and because our primary interest is in establishing the JUST scale’s psychometric properties, we included all participants in subsequent analyses. Analyses using only the death-qualified mock jurors (n = 386) showed the same pattern of results.

4 The other scales, such as several measures of participants’ religious beliefs, were included for a separate purpose and are therefore not discussed here (see West et al., 2020).

5 Unlike Study 1, there were not enough minority participants to conduct a meaningful comparison of individual minority groups; minorities were therefore combined into a single non-White group for analysis.