The Illegality Defence in the Law of Negligence after Miller v. Miller

In 1991, the High Court delivered judgment in Gala v Preston. This landmark case concerned the defence of illegality to liability arising in the tort of negligence. It established that parties to a joint illegal enterprise do not owe duties of care inter se if the nature of the enterprise is such that it would be "impossible" or not "feasible" to ask how the reasonable person would have acted in their circumstances. The High Court recently reconsidered the defence in Miller v Miller. This was the first opportunity since Gala that the court has had to address this defence directly. The High Court replaced the principle in Gala with a test based on the legislature's purpose in creating the offence that the plaintiff committed. This article delineates that approach and identifies some difficulties with it.