Law and order effects: on cognitive dissonance and belief perseverance

Abstract

Order of evidence presentation affects the evaluation and the integration of evidence in mock criminal cases. In this study, we aimed to determine whether the order in which incriminating and exonerating evidence is presented influences cognitive dissonance and subsequent display of confirmation bias. Law students (N ¼ 407) were presented with a murder case vignette, followed by incriminating and exonerating evidence in various orders. Contrary to a predicted primacy effect (i.e. early evidence being most influential), a recency effect (i.e. late evidence being most influential) was observed in ratings of likelihood of the suspect's guilt. The cognitive dissonance ratings and conviction rates were not affected by the order of evidence presentation. The effects of evidence presentation order may be limited to specific aspects of legal decisions. However, there is a need to replicate the results using procedures and samples that are more representative of real-life criminal law trials.

Juror perceptions of opposing expert forensic psychologists: Preexisting attitudes, confirmation bias, and belief perseverance.

“…The jury will be required to make a global judgment based on their evaluation of all of this evidence, and research shows that the order in which opposing evidence is presented will matter (Charman et al, 2016(Charman et al, , 2019. In studies addressing order effects, some results indicate a recency effect-the last piece of information considered will have the most considerable effect on the jurors' judgments of the defendant's guilt (e.g., Charman, 2013;Maegherman et al, 2021). Other studies suggest that the evaluation of the first piece of evidence will frame jurors' judgments about all subsequent pieces of evidence.…”

“…So, decisions of guilt tend to be consistent with whatever information jurors considered first ( confirmation/contextual bias and primacy effects, e.g., Marksteiner et al, 2011). Other researchers focus on the strong influence of preexisting opinions on global case judgments about the defendant’s guilt (confirmation/contextual bias and belief perseverance; e.g., Maegherman et al, 2021).…”

“…Research also shows that presenting opposing expert testimony will impact jurors' decisions. However, the exact nature of this effect is still uncertain, with researchers often concluding that more work is needed to decode the mixed results (Charman et al, 2016(Charman et al, , 2019Maegherman et al, 2021). For example, in one study, participants who read testimony from two opposing anthropomorphic facial comparison experts (an uncommon, very subjective practice) demonstrated that they responded to statements about the reliability of the forensic method from the expert, evidenced by a reduction in guilty verdicts (Scobie et al, 2019).…”

“…Because attitudes develop over a long period, often without awareness, these strong cognitive patterns are notoriously challenging to counteract (Bornstein & Greene, 2011). Thus, we can expect verdicts in criminal trials featuring defendants with psychological disorders to be affected by the preexisting ideas each juror has about mental illness, in addition to other potential sources of bias (Charman et al, 2016; Maegherman et al, 2021).…”

“…This is different from contextual and confirmation bias effects, which do not predict a strengthening of the initial opinion when exposed to incongruent information. Incongruent information is discounted or explained away, allowing individuals to preserve their initial view without feeling concerned or cognitive discomfort ( cognitive dissonance; Maegherman et al, 2021). Understanding the role of preexisting attitudes in such cases and how existing opinions interact with new information is essential to comprehend juror decision-making processes and evaluation of information.…”