The Effect of an ‘Appearance, Presentation and Demeanour’ Instruction on Credibility and Deception Judgments in Mock Refugee Status Decisions

Abstract

Can a written instruction convince refugee status decision-makers not to rely on a claimant’s ‘appearance, presentation, and demeanour’ in judging the claimant’s credibility? How else might such an instruction affect the decision-makers’ deception judgments? This study explored the effects of an APD instruction on the judgments of lay decision-makers making credibility judgments in a simulated refugee hearing (n=275). It sought, by means of an experiment, to quantify the instruction’s effects both on decision- making outcomes and on the written reasons that the decision-makers offered to justify their conclusions. The APD instruction in our study had no significant effect on whether participants judged the claimant to be credible or deceptive, how confidently they reached either kind of conclusion, or how thoroughly they justified their reasoning. Those who received the instruction, however, cited APD factors significantly less often in supporting their judgments. Under this study’s simplified experimental conditions, the APD instruction may have caused decision-makers, consciously or otherwise, to suppress the fact that APD factors had influenced their thinking, driving these factors underground. In real life, this kind of suppression would have serious consequences for the rule of law, as it would immunize flawed reasoning from appeal or review. This study’s findings, which have implications for credibility assessment in other legal settings, call into question the received wisdom that written instructions are an effective way to dissuade decision-makers from relying on unsound deception inferences