In a recent paper in the Yale Law Journal, Malcolm Thorburn argued that to enjoy a justificatory defence in the criminal law is to have a normative power that is exercised in the circumstances which give rise to the justification. He also argued that where such powers are conferred on private citizens, those citizens should be understood as acting as public officials pro tempore when they exercise them. In this extended reply, I resist both propositions and reply to some of (...) the criticisms that Thorburn makes of my own rival views. I also take the opportunity to explore, philosophically, some of the criminal law relating to consent, self-defence and arrest, and to discuss the connections between the debate over the nature of criminal-law justifications and the debate over the nature of law. (shrink)