PRIVACY REGULATIONS

[Jonathan Rochkind]

There is no requirement to identity yourself, but the police will regularly
lock you up in jail until you do identify yourself. They can't _force_
you to identify youself, and you can't go to trial for not doing so
(partially because they dont' know who you are, but even if they later
find out for other means), but nevertheless police departments everywhere
will lock you up until you provide ID if you are stopped for a traffic
violation.
 
There is a guy around here-abouts who will routinely gets stopped for
speeding and refuses to show ID out of principal. They put him in jail.
He's tried to sue them, and lost. 
 
If it made it all the way to the supreme court, I'm not sure what they would
decide. But the point remains, in real life, they put you in jail. Just
be aware of it.