Some states don’t allow bounty hunters to be there, so if you go there to pick somebody up, you’re breaking the law just by picking that person up in that state. It is legal to cross the line as long as you’re in a state that allows you to be a bail bondsman.
Illinois and Texas, for example, have their own rules. If you’re driving through those states on your way back without following their rules, you could get in trouble even though it didn’t happen in that state. You can go bounty hunting in Texas, but you need to be accompanied by a state-licensed bail bondsman or an agency. You can’t just come in and cowboy it up there.