Basic Law for the Federal Republic of Germany
The Federal Constiutional Court (German: Bundesverfassungsgericht) protects the constitution by banning laws which break the constitution. There are "eternal clauses" in the constitution which the court will protect even by banning constitutional amendments (laws to change them). Article 1, about human life and dignity, and article 20's basic principles are protected from change. This is to make sure nothing like the Nazi period happens again. The Nazis were able to pass an Enabling Act which allowed Hitler to rule by decree.