The comparison between Auschwitz as a paradigm of exclusion and some implications of contemporary European immigration policies has been very often drawn referring to several aspects, as the “annihilation” of human beings as subject of rights or the generalization of state of exception as a practice of government. It is however very important, from a legal perspective, to analyze the peculiar characteristics of Authoritarian and Democratic States, considering both the general level (that of fundamental constitutional principles and rights) and the specific one (that of immigration law and legal status of foreigners). Even if originally ambiguous – as pointed out by Hannah Arendt asserting that a man who’s not also a citizen is not really protected by human rights law – constitutional declarations of human rights succeeded in determining a constitutional status for foreigners in European countries. Especially Constitutional courts – checking the constitutionality of laws and interpreting evolutionarily constitutional norms – made it possible to extend fundamental rights and constitutional guarantees even to foreigners, in some cases declaring restrictive laws on immigration and legal status of foreigners unconstitutional. Examining the first decisions of the French Conseil Constitutionnel and the German Bundesverfassungsgericht on immigration and constitutional status of migrants it is possible to point out three main spheres in which courts succeeded in narrowing state power of determining conditions of entry and stay of foreigners in the national territory: the restriction of state power of expulsion; the constitutional foundation of residence and legal status of foreigners; the recognition of a constitutional right to family life and family reunification.