Abstract
This chapter explores, in a roundabout way, whether Kant’s legal philosophy relies on his mature ethics of autonomy and respect. The normativity of the law must be externally enforced by coercive measures. The proportionate and credible threat that transgressions will be punished acts as a deterrent and make the rights of individuals comparatively secure – the law is occasionally broken. Now, the Kantian state does not concern itself with why in particular citizens break or comply with the law. In that sense, Kant’s philosophy of law does not rely on his ethical theory or moral psychology. But agents must be in a position to comply with the law. They must face a meaningful choice, which can only be secured by the availability of the motive of ethics: respect for the law. Without respect, agents would be exposed to prudential considerations only. Those who break the law take their criminal act to be prudentially justified. Viewed from this limited perspective, their actions turn out to be imprudent if they are punished for them. But punishability and imprudence are different. So, making what the law prohibits properly illegal requires an ethical foundation after all.