The power of the Judicial Branch to overule a law enacted by other branches with higher democratic legitimation constitutes a central feature of constitutional democracies. Nevertheless its justification beyond a positivist approach is complex, since judicial review envolves a paradox: at the same time that courts seem to be vital to democracy they also impose limits. In this dissertation is proposed the discussion of the counter- majority difficulty of the judicial review from the american and european doctrines point of view, and a detailed analisys of the perpectives that try to overcome its democratic deficit, proposing one justification that reconciles it with the democratic ideal. The conclusion offered considers the institution of judicial review in a general level, and is focused in a deliberative democracy basis that promotes an equilibrium between human rights and popular sovereign.