The task used most widely to assess recognition of false belief in self and others is the 'Smarties' unexpected contents task. Amongst individuals with and without autism, the Self and Other-person test questions of this task are of an equivalent level of difficulty. However, a potential confound with this task may allow the Self test question to be passed without false belief competence. Three groups of participants (with autism, developmental disability and typical development) undertook a new unexpected contents task which did not suffer from this confound. The main finding was that participants with autism performed significantly less well on the Self test question than the Other-person test question on this new task. Individuals with autism may have greater difficulty representing their own beliefs than the beliefs of other people.