"What makes you think you'll be safe if you leave the city then? I'm sorry son, if you leave the city you will be placed under arrest. That is the conditions of our letting you go, we have an investigation here, we can't let suspects leave the city."
((At least I don't think they let people leave the city...if your a suspect they can't allow you to slip away, you could flee the country for all they know. Plus what makes you think the detective cares about some guy hunting you?))