OK, but if something happens and you're unconscious and bleeding and such ... the police probably won't think to find it there at first, and even when/if they do look they'll initially disregard it as they continue looking for your ID. They won't go looking at flash drives until they're really desperate, and it may very well be that it isn't done by the first responding police at all, but by the computer guys back at the station days later.

Personally, I think you'd do better to put all that information on a card that's the size of your ID (or at least the really important stuff), laminate it (or at least cover it with clear packing tape) so it's water proof and put that in your bag. They can read that *without* a computer and it would match what they're actually looking for enough that they'd actually read it.

Also, USB drives are an effective vector to attack computers. Such a drive could possibly be used to hack the police computers. I'm not saying that you'd do this, but the police who work the streets may very well have a policy not to stick anything in the USB ports of their computers. They may not even have USB ports at all, or they may be disabled -- leaving such analysis to the guys who know what they're doing back at the station.