> The police banned speaking any language other than German or English.

Incorrect. That was a court order, because people were quite obviously subverting the prohibition of calling for genocide by using languages law enforcement does not understand.

> I don't actually know any Jews (or Muslims),

I know both Jews and Muslins: you are incredibly wrong.

"You are incredibly wrong." is such a great rebuttal. It applies in any situation and you don't even have to bring any evidence.

My rebuttal to your rebuttal: You are incredibly wrong.

(And who cares if it was the police or the courts? Both are branches of the government. And if the court order was as you described, then why did the police march someone off in handcuffs for speaking Arabic privately to another person who spoke Arabic?)