R v Bailey [1983] 1 WLR 760

Bailey, who had diabetes and used insulin, visited the man with whom his former partner had begun a relationship. After asking for sugar and water, Bailey later struck the man with an iron bar. He said that insufficient food after taking insulin had caused hypoglycaemia and left him unaware of the assault. Medical evidence addressed the need to balance insulin with food. The trial judge told the jury that self-induced automatism was unavailable, and Bailey was convicted of wounding with intent. His appeal challenged that categorical treatment of the defence.

Did contributing to an episode of hypoglycaemia by failing to eat necessarily exclude automatism, and how did the distinction between specific-intent and basic-intent offences affect that question?

The Court of Appeal rejected the proposition that every self-induced episode automatically excludes the defence. The relevant mental element of the charged offence still required examination. For a basic-intent offence, responsibility could arise where the defendant recklessly brought about the state, including awareness that the failure to eat might make him aggressive or uncontrolled. Mere contribution to a medical episode did not establish that fault without further analysis. Nevertheless, Bailey's appeal was dismissed on the evidence and the court's assessment of the conviction. The discussion of a potentially available defence must therefore be separated from the actual outcome: the court did not acquit him simply because hypoglycaemia was asserted.

Self-induced automatism is not excluded merely because the defendant contributed to a medical episode. The offence's mental element and any relevant recklessness in causing the condition must be examined; a specific-intent charge cannot be resolved by a blanket rule about self-inducement.

The case is important when comparing hypoglycaemia linked to insulin and insufficient food with conditions discussed under insanity. It also shows why medical causation and legal fault are separate questions. An answer should establish a proper evidential basis for automatism, identify the offence charged, and consider what the defendant knew about the risk of becoming uncontrolled. Saying that the defendant failed to eat is not a substitute for analysing the relevant mental element.