The Sexual Offences Act 2003 introduced a new statutory offence of ‘sexual activity in a public lavatory’ into English law. Although written as a gender-neutral offence, the statute was formulated and enacted on the basis of concerns about male homosexual sexual activity in public lavatories (‘cottaging’). This paper examines the justifications for, and implications of, the legislation. It considers the main arguments made in support of the offence and situates these within established moral, legal, and social debates about homosexuality. The paper considers the relationship between conceptions of public and private morality in relation to the legal regulation of homosexual sex. It goes on to explore the complex nature of regulating public sex in relation to sexual practices which often maintain high degrees of privacy. The final part of the paper argues that the legislation is largely in contradiction with the realities of police work and contemporary law enforcement.