I wanted to say in German the following sentence:
He is a state approved male nurse.
Google translate came up with:
Er ist ein staatlich anerkannter Krankenpfleger.
I am wondering why 'staatlich' is not inflected. After attempting to understand the information on canoo.net I have concluded that 'staatlich' is an invariable adjective i.e. one that does not have comparative and superlative forms. That makes sense, but if that is true, then it should surely follow that the adjective 'anerkannt' should also remain uninflected, as there are no comparative or superlative forms of that either.
So the question is, why is 'staatlich' not inflected when 'anerkannt' is?