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Not guilty on grounds of insanity

A short ‘reading list’ on the recent case of Teancum Vernon Petersen-Crofts and the issues raised by the use of the insanity defence

Not guilty on grounds of insanity

This week (February, 2021) there was an interesting case (The State of Western Australia v Teancum Vernon Petersen-Crofts (Indictment number INS PER 94/2019) in which the defendant was found ‘not guilty on grounds of insanity’.

The insanity defence is one of the most widely debated and most frequently misunderstood issues in the criminal justice system.

I’ve put together a short ‘reading list’ for those of you who would like to learn more about the case, and the issues raised by the use of the insanity defence.

In a later Blog I’ll explore the links between investigative interviewing and mental illness.

I hope you find this helpful.

The case of Teancum Petersen-Crofts (WA)

Perpitch, N. (2021, February 15). Teancum Petersen-Crofts found not guilty of murdering mother, sister and half-brother on grounds of insanity. ABC News.

McNeill, H. (2021, February 15). ‘We have failed you’: WA judge finds mentally ill teenager not guilty of murdering his family. WA Today.

Background reading on the insanity defence

Collins, P. (2021a, February 10). Investigating insanity cases: Part one Blue Line.

Collins, p. (2021b, March 15). Investigating insanity cases: Part two Blue Line.

Loughnan, A. (2015, November 6). How the insanity defence against a murder charge works. The Conversation.

Malcolm, L. (2015, June 10). A plea of insanity: mental illness and the criminal justice system. ABC.

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I’d love to hear what you think about this case.

You can write to me - - and let me know what you think.

Other resources

If you’ve enjoyed this Blog post, I invite you to check out Forensii offers online forensic psychology education and is the essential resource for information on investigative interviewing.

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