Thought Crime and the Treason Act 1351

Abstract

Has there ever been a law criminalizing mental states in themselves? We show that there has been, and still is: the Treason Act 1351. We argue for what we call ‘the Mental Interpretation’ of the Act, over against the interpretation that it criminalizes a complex of a mental state and an ‘overt act’. We also provide authority for the stronger thesis that the overt act functions purely as evidence for the mental state. We discuss other laws in various jurisdictions that have historically criminalized mental states in themselves. We conclude by considering the objection that the European Convention on Human Rights rules out our interpretation.