this girl I know told me that she was walking downtown once with her dad, and a cop started to ticket them for jaywalking. Her dad got belligerent and said "what if I don't pay, are you going to put a boot on me?" The cop had no good answer other than getting pissed.
Since you don't need a license, they can't even require you to produce ID and I know people who've successfully given false names. I used to work for a courier company which had a trophy wall where people hung up their tickets, rather than ever sending them in for payment. On the other hand, if they want to be dicks about it, they can detain you for hours if they want to and even take you to the station in order to "verify identity."
in DC, they can also impound your bike if it's not registered, but again they only do that if they want to be dicks, and most DC cops won't be a dick to you unless you're a dick to them.
For the most part, though, these laws don't really matter much unless you harm someone, in which case you're fucked. Momentum equals mass times velocity, thus if you weigh 150 lbs and you're going down a hill on your bike at 30 miles an hour, and you hit an 80-year old woman crossing the street, you're likely gonna kill her or put her in the hospital. And if the cop who responds notices you're reeking of alcohol and determines that you were riding drunk, you're likely going to jail.
