Memory difficulties following traumatic experiences have been found to result in testimonial inconsistencies, which can affect credibility judgements in asylum decisions. No investigations have looked into how/whether the behavioural sequelae of Post-Traumatic Stress Disorder [PTSD] affect decisions. This study aimed to investigate this by looking at whether observable symptoms of PTSD can be confused with perceived cues to deception. An actor performed four versions of a fictional ‘asylum interview’ that contained differing levels of pre-defined ‘deception’ and ‘trauma’ behaviours. Four groups of students (total n=118) each watched a different interview. They gave subjective ratings of credibility, plus quantitative and qualitative information about the factors that influenced their judgements. Despite the content of the interviews remaining the same, significant differences in credibility ratings were found between interviews; with the interview containing both ‘trauma’ and ‘deception’ behaviours being rated as significantly less credible than the interview containing only the PTSD behaviours. ‘Emotional congruence’ was conceptualised as an important factor in influencing credibility. Results are discussed in terms of possible heuristics involved in judgements of an asylum-seeker population, as well as implications for vulnerable asylum seekers whose symptoms do not conform to stereotypes. Limitations and avenues for future research are highlighted.