Courts' misplaced confidence in psychiatric diagnoses.

In considering psychiatric evidence, criminal justice systems make considerable use of labels from official psychiatric classificatory systems. There are legislated requirements for psychological and/or behavioural phenomena to be addressed in legal tests, however medico-legal use of the current categorical diagnostic frameworks which are increasingly complex is difficult to justify. The lack of validity in large domains of the present classificatory systems is now more openly acknowledged, prompting a critical rethink.