The US doesn't really have the distinction legally, it's from English Common law. Something is illegal if it breaks criminal law (aka you can be punished for i

The US doesn't really have the distinction legally, it's from English Common law. Something is illegal if it breaks criminal law (aka you can be punished for it). Unlawful just means something is not lawful. If you take something reasonably believing it is yours (pickup the wrong coat), you've acted unlawfully: you can be made to give the coat back or pay recompense. If you take a coat knowing it isn't yours, that's illegal. Everything illegal is unlawful, but not everything unlawful is illegal.