100% of Hitler's reign was legal. Everything he did was 100% legal.
Morality is and must be above laws.
(Edit: ChatGPT reminds me that Hitler's post-1933 actions were legal; the earlier (and failed) "Beer Hall Putsch" was illegal.)
Looking back it seems crazy that he only got one year in jail for the failed Putsch.
A Brown shirt killed by a communist/socialist was always illegal, but a communist/socialist killed by a brown shirt was always self defence and always legal.
That's why the rule of law is so important, and that's why it shouldn't have exceptions for anyone, even policemen (arguments could be made for elected people as long as they are elected though).
Which is what republicans and Trump have been doing the past 10-15 years. Just need to look at how the supreme court is behaving as of late.