Legal Case Summary
Bratty v Attorney General for Northern Ireland [1963] AC 386
Failure to discharge onus of proof in relation to defence of automatism
Facts
The appellant (B) was convicted of the murder of an 18-year-old girl. In his statement to the police, he said that he had been overcome with a “terrible feeling” and a “sort of blackness” during the event. At trial, B relied upon the defence of automatism as a result of psychomotor epilepsy but the trial judge dismissed this defence and did not submit it to the jury.
Issues
On Appeal to the House of Lords, B argued that the trial judge was wrong to dismiss the automatism defence. It was argued that the burden of proof was on the Crown to prove that (i) the acts were conscious and voluntary beyond reasonable doubt; (ii) there was a body of evidence indicating the act was not voluntary or consciously done and (iii) this body of evidence should have been left to the jury. The Crown submitted, inter alia, that where the defence of automatism is based on an internal factor then the onus upon the accused is the same as on a plea of insanity.
Decision/Outcome
The trial judge was only under a duty to leave the issue of automatism to the jury where the defence had left a proper evidential foundation for doing so. The trial judge in this case was right to not leave the defence to the jury as the only cause alleged for the act in question was an internal factor i.e. a defect in reason from disease of the mind. Furthermore, as B was deemed to have been sane and reasonable at the time of the killing, he could not be said to lack intent and, therefore, there was no question of a reduced manslaughter charge.
Updated 19 March 2026
This case summary remains accurate. Bratty v Attorney General for Northern Ireland [1963] AC 386 continues to be good law and is regularly cited in relation to the defences of automatism and insanity in criminal law. The core principles established by the House of Lords — including the distinction between insane and non-insane automatism, the internal/external cause distinction, and the requirement for a proper evidential foundation before the defence is left to the jury — remain authoritative and are consistently applied by English and Northern Irish courts.
It should be noted, however, that the law of insanity in England and Wales has been subject to ongoing reform debate. The Law Commission published a report in 2023 recommending significant changes to the defences of insanity and automatism, including replacing the M’Naghten Rules with a new statutory framework. As of the date of this update, these recommendations have not been enacted, and Bratty therefore remains the leading authority on automatism. Students should monitor legislative developments in this area, as reform could materially alter the legal framework within which Bratty operates.
