We examined whether theory of mind difficulties often considered to characterise autistic individuals impair their ability to detect the presence of dodgy or suspicious behaviour in interactions, thereby rendering them especially vulnerable to becoming involved in criminal activity or being victimised. Using a signal detection theory approach, we compared autistic (N = 72; Verbal Comprehension Index = 88-122, M = 106.6) and non-autistic (N = 70; Verbal Comprehension Index = 86-120, M = 104.4) adults' ability to detect dodgy or suspicious behaviour across a broad array of scenarios (N = 136). Although theory of mind performance was poorer for the autistic group, frequentist and Bayesian analyses indicated there were no group differences in either the standard measures of discrimination performance obtainable using a signal detection theory approach or in terms of a bias towards reporting dodgy behaviour. Furthermore, there was no indication of a relationship between dodginess detection and autistic traits. However, regardless of group membership, theory of mind difficulties were associated with poorer discrimination of dodgy behaviour, highlighting an individual difference variable that may increase the vulnerability of both autistic and non-autistic individuals to involvement in some form of criminal activity or to becoming a victim of crime.