My nephew came home from school today and he was telling me how a police man came to his class, and he told them if they were in trouble, a police man could always help them. But also that sometimes people who aren't really police try to dress up like them and tell you that they're the police. That is why you should always ask to see their badge.
But this got me thinking. Do you think Aurors and Hit Wizards and similar people have special badges to carry to identify themselves with? I would think the wizarding world could also have problems of people trying to impersonate government officials.