Crime Offender With Mental Retardation: A Case Report

Objective: This case report aims to discuss the diagnosis of mental retardation as insanity defence in a crime offender. Methods: We report a gentleman who committed murder and rape 9 years ago, and currently being treated at a mental institution. Results: Patient was certified to have mental retardation, and was pleaded on the defence of unsoundness of mind because he had defect of reason at the time of alleged offence. Conclusion: Mental retardation does fulfil the McNaughton’s rule. Unsoundness of mind becomes the insanity defence even for murder under section 84 of the Penal Code.