This article examines the interplay between human rights law and humanitarian law in relation to riot control agents (such as tear gas), expanding bullets and plain-clothed forces. While outlawed under humanitarian law, they are widely used by police in peace time and not subject to similar bans under human rights law. Surprisingly, the legal challenges arising from their potential use in modern military operations have so far received only limited scholarly attention. This article tries to fill that gap and endeavours to contribute to the broader debate on the interplay between human rights and humanitarian law in (international) military operations. Drawing on the relevant preparatory works as well as subsequent practice and recent jurisprudence, this article shows that the humanitarian law rules on the use of riot control agents, expanding bullets and plain-clothed personnel provide for a sufficiently broad law-enforcement exception. Hence, they can be used in times of armed conflict outside of combat operations.