Judges and courts have the constitutional duty of protecting the legitimate rights and interests of citizens and, in their relations with the Public Administration, of doing so by reviewing the legality of administrative action. The jurisdictional function optimizes all legal conditions -in terms of independence and impartiality, procedural guarantees...-, to ensure that judicial bodies make justice in a specific case. Judicial review does not impede the legal configuration of administrative control mechanisms oriented to the same purpose. The lawmaker can set up administrative bodies and agencies with a special statute similar to that of the judicial bodies, conferring legality control functions aimed at providing justice. The truly inalienable constitutional limit is that the eventual provision of these control mechanisms cannot prevent access to the jurisdiction to review the decision adopted within it. A renewed administrative justice system must find in the complementation of the function between judicial bodies and quasi-jurisdictional administrative bodies, the basis to guarantee the protection of citizens in terms of access, procedural guarantees, costs and time.