Status: We published a scoping paper on 18 July 2012
When should a person not be criminally liable because of their mental condition at the time they committed an alleged offence? This is the question posed by what is called the defence of “insanity”.
Similarly, a person might not be criminally liable because they lacked conscious control of their actions at the time of committing the alleged offence for a reason other than their mental condition. This might amount to a defence of "sane automatism" under the current law.
The current rules that govern the insanity defence (also referred to as "insane automatism") date from 1843. They have been widely criticised for a number of reasons:
it is not clear whether the defence of insanity is even available in all cases
the law lags behind psychiatric understanding, and this partly explains why, in practice, the defence is underused and medical professionals do not apply the correct legal test
the label of “insane” is outdated as a description of those with mental illness, and simply wrong as regards those who have learning disabilities or learning difficulties, or those with epilepsy
the case law on insane and non-insane automatism is incoherent and produces results that run counter to common-sense
There are also potential problems of compliance with the European Convention on Human Rights.
We are convinced, on the basis of our research, the vast wealth of academic literature and the previous reform proposals that there are many cogent criticisms that may be made of the current law in principled terms.
There is, however, less evidence that the defence causes significant difficulties in practice. The empirical data suggest that there are only a very small number of successful insanity pleas each year (under 30). In our scoping paper we asked questions to discover whether the current law causes problems in practice, and if so, the extent of those problems. The responses to this paper will inform how we take the project forward.
We anticipate publishing the next paper in this project in the summer of 2013.
We have a separate project on the related problem of unfitness to plead.