Quality vs. quantity: the effect of relationship and number of corroborators on alibi assessments

Abstract

The effect of the suspect-corroborator relationship and number of corroborators on alibi assessments was examined across two experiments. In both experiments, we explored the effect of relationship type and number of corroborators on believability, likelihood of guilt, and decision to retain the suspect as the primary suspect; we increased the social distance between the alibi provider and suspect and the size of difference between the number of corroborators in Experiment 2. Collectively, our results support Olson and Wells’ taxonomy of alibi believability as (a) any form of person evidence mitigates pre-alibi judgments of guilt (although there is a ceiling effect), and (b) alibis corroborated by non-motivated others were judged more favourably than those corroborated by motivated others. Our results lend support toward extending the original taxonomy to include the number of corroborators. The implications for the alibi assessments are discussed.

Key words:

• alibi assessment
• alibis
• corroborator
• believability
• investigations
• policing
• wrongful convictions

Ethical standards

Declaration of conflicts of interest

Joseph Eastwood has declared no conflicts of interest

Christopher J. Lively has declared no conflicts of interest

Brent Snook has declared no conflicts of interest

Mark D. Snow has declared no conflicts of interest

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee at Ontario Tech and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study

Notes

1 Qualtrics was responsible for administering the compensation to participants in-house. Therefore, we do not know the exact amount of monetary incentive that was provided for participation.

2 See Footnote 1 regarding same issue.

Additional information

Funding

Support for the research reported in this paper was provided to the first and third authors by the Social Sciences and Humanities Research Council of Canada [grant number 430-2014-00860].