I know that I’m behind the times, but how on earth can sharia law be put into effect anywhere there’s not a Muslim controlled state legislature? (In other words, Muslims can choose to obey it, but how would it impact my family?)
Orthodox Jews have courts of law, called batei din, which have jurisdiction only on Jews who choose to obey them. And, of course, various Christian sects sometimes turn temporal disputes over to church authorities. What’s the difference with Muslims adhering to their laws?
Muslims impose sharia on anyone entering the zone they have taken over, muslim or not. Even the police won't go there unless there are serious reinforcements.
Firemen responding a structure fire in No Go Zones cannot safely proceed without substantial police defensive units. Even when trying to help residents by putting out a fire, they are extremely liable to be physically attacked.
Lots of documentation here:
https://www.meforum.org/mef-online/europe-is-turning-into-one-big-no-go-zone