This dissertation presents an answer to the question of why modern legal institutions and the idea of citizenship are important for leading a free life. The majority of views in political and legal philosophy regard the law merely as a useful instrument, employed to render our lives more secure and to enable us to engage in cooperate activities more efficiently. The view developed here defends a non-instrumentalist alternative of why the law matters. It identifies the law as a constitutive feature of our identities as citizens of modern states. The constitutivist argument rests on the (Kantian) assumption that a person’s practical identity (her normative self-conception as an agent) is the result of her actions. The law constitutes these id...