Well, that was the point of my previous post.
His appointoment as chancellor was legal on paper. Which is a weak argument considering the situation that Germany was in. But it's technically true.
...and that's where it ends, really - his decision to usurp Hindenburg's powers after his death (into a combined office of chancellor/president that he called "Fuhrer") was clearly illegal, as were most of the other things he did.
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