Suspicious minds? Empirical analysis of insider witness assessments at the ICTY, ICTR and ICC

Abstract

The testimonies of insider witnesses are often key to prosecutions of international crimes, despite significant trustworthiness concerns. However, we know little about the practice of judicial assessments of insider testimonies, that is, which factors the judges consider relevant to relying on insider testimony. With this article, we set out to provide a comprehensive, explorative examination of the insider witness assessment factors used by the trial judges at the International Criminal Tribunal for the former Yugoslavia, the International Criminal Tribunal for Rwanda and the International Criminal Court in 1996–2019. By using multiple correspondence analysis, we show that the factors related to insider witness assessment outcomes are generally similar across the tribunals and tend to focus on the contents of the testimonies, with less attention given to credibility or competence concerns. This research constitutes the first systematic quantitative analysis and cross-institutional comparison of insider witness assessment practice at an international level.

What matters for assessing insider witnesses? Results of an experimental vignette study

“…Factors. The two factors, witness quality and information quality, were developed on the basis of prior findings on judicial assessments of (insider) witnesses (Chlevickaitėet al, 2020(Chlevickaitėet al, , 2021Combs, 2010;Smith, 2020;Zahar, 2010) as well as other research on witness assessments, including legal and forensic psychology findings (e.g., Hauch et al, 2017;Hudson et al, 2019;Leal et al, 2020;Novo and Seijo, 2010;Volbert and Steller, 2014).…”

“…Information quality is focused on the quantity and verifiability of details, in line with the theory that truth-tellers would provide more verifiable detail than liars, and findings of ICCT case law analyses (Chlevickaitė et al, 2021; Nahari and Nisin, 2019). High information quality statements contain (i) verifiable details: precise dates, numbers of individuals involved, and names of members of the group and (ii) information specific to the crime: chain of command and decision-making.…”

“…Certain aspects of credibility assessments are typically based on the evidence available to the decision-makers: e.g., documentation on victimisation, links to religious groups and memberships of certain organisations. However, they also commonly refer to more subjective indicators stemming from the impression the witness had given during testimony, such as the witness's performance or behaviour on the stand (Chlevickaitėet al, 2021;Kelsall, 2009).…”

“…On top of that, insider witnesses have also been found to harbour feelings of animosity towards the accused or other (former) members of the organisations, or, on the contrary, were motivated to exculpate others and, consequently, themselves (Roberts, 2012; Vukušić, 2022). In line with this complicated picture, case law analyses have revealed that the judges more often than not dismiss at least parts of insider witness testimonies (Chlevickaitė et al, 2021).…”

“…Though lacking a consistent definition, at International Criminal Courts and Tribunals (ICCTs) ‘insiders’ commonly share the following attributes: they (i) have worked closely with the accused (Sluiter et al, 2013) and have potentially been involved in the commission of the crimes (Harmon and Gaynor, 2004), and (ii) provide information on the accused's criminal conduct to the court (Stepakoff et al, 2014). Insiders were relied upon extensively in majority of trials at ICCTs, including the pivotal trials of Charles Taylor, the former president of Liberia at the Special Court for Sierra Leone (Pamsm-Conteh, 2017); Radovan Karadžić, the former president of Republika Srpska at the International Criminal Tribunal for the former Yugoslavia (Vukušić, 2022); and all the cases that have been litigated at the International Criminal Court (ICC) to date (Chlevickaitė et al, 2021). This practice did not proceed without trouble as major international crimes cases have fallen apart due to insider witnesses recanting their testimonies, or due to a lack of trust placed upon them by the judges at trial (de Brouwer, 2015; Lawson and Bartels, 2019; Mueller, 2014).…”