Well, as a german, where this happens often enough: If a law gets truck down by the Federal Constitutional Court ("Bundesverfassungsgericht") as being in violation of the constitution, this universally can be seen as a bad job performance for the lawmakers.
They know the law was in violation of the constitution, still they agreed upon it. It's their fucking job to make sure laws are not in violation of the constitution.
This clearly justifies a strike.