> Imprisoned Vampire Elected Mayor

That's not even (necessarily) a bug: whether convicts can win/hold elected positions is a aspect of applicable law (albeit a weird one), vampires (IIRC) have high social stats and skills and so are well-postioned to win elections in general, and dwarves (and for that matter humans) don't necessarily update their opinion of someone just because they were convicted of a crime (especially if they don't hear about the conviction, which (knowledge transmission) I recall was added to the game modeling at some point). So this is like a headline "Bob Smith Convicted of Murder; Wins Mayoral Election Anyway", which seems weird-but-possible in real life.

Yeah exactly. Also top tip is if you actually catch a vampire in DF a known thing is to imprison them in a room with all your switch levers in and a desk and chair so you can make them your accountant. They don't kill anyone that way and can do useful work.