The aim of this article is to describe two legal cultures, namely the culture of authority and the culture of justification, as formulated by David Dyzenhaus. This distinction between legal cultures proposed by the Canadian theorist of law makes an interesting contribution to the discussion on how to make headway with the problem of determining the limits of public authority and, consequently, the problem of implementing the principle of the separation of powers in such a way that conflicts do not arise. In general, with the culture of authority, justification of the actions of an authority is necessary only when it is being established, and once its authority has been established, the authority sees no further need to justify its decisions...