It is illegal to sing loudly off-key on a public street at night.

The Law

Before the era of noise-canceling headphones and soundproofed homes, loud drunks walking home from the tavern were a major nuisance. This outdated disturbance of the peace statute specifically targets boisterous, late-night vocal performances. If you lack musical talent and volume control, you could historically be fined for ruining the neighborhood's sleep.