Sorry if this is the wrong StackExchange, but I figured it was more appropriate here than on Writing. I'm writing a story with a sequence where city authorities decide to block travel out of the city to contain an epidemic. The POV character knows that the epidemic isn't what it seems and that they need to evacuate the city (she has evidence), and has to convince them to lift the quarantine.
Question is: who would be in charge of these decisions? The sheriff? The mayor? Would the character have to convince a sort of council?
If it varies by country, I prefer a US answer; if it varies by city, any answer that won't make me sound ignorant is fine.