“I’m sorry sir, it is illegal to serve medium-rare burgers in this city.”
I can’t really fault my waitress for uttering this common misconception. Like many, I used to think that it is illegal to serve hamburgers that are raw in the middle. It is not. The health authorities do not have such a law in the books. What is stopping most restaurants from giving you the option of ordering a rare or medium-rare burger has nothing to do with the legality of the act, but from their own distrust of their source of ground beef. Most burger joints will not take chances as they get their ground meat from large factory operations whose quality control is beyond their reach.