Can your employer take money out of your bank account?

[Smitty]

Let's say you have direct deposit. If your employer makes a mistake and over pays you, do they have the legal right to take that money back out of your account without your approval? I know that if you don't give it back, things would be a bit unpleasant on the job, but there's no way they should be able to just go in and take money from your account without your OK, right?