Well, a FOIA request is a federal thing... so probably doesn't apply. That said, states have different information acts so you'll need to look into what applies in your area. These are routine paperwork things that don't tick off the cops or anyone else. Not generally, and if they do it's the cop's problem, not yours. There is a possibility it will cost you per page, though, which can add up. Ask for your information to be delivered through email or on a compact disk, that should help cut down on costs.I would only do that after you'd tried all else that is possible to get info and compliance from the police....you don't want a war with them too.
HOWEVER this may very well be being handled as a currently open case, in that situation you'll (rightly) be told they can't give you very much information at all. And probably none. Which brings me back to my original advice: LAWYER UP, COWBOY!
