[refurb]

Don't be so sure! I read the SF Police blotter and see plenty of people arrested for suspicion of auto theft because they had "shaved keys" with them.

Depending on how saavy the local police are, you may get more attention then yoi want if the cops look close enough at your keys.

[peterwwillis]

You can't be arrested for suspicion alone, and bump keys aren't illegal according to California statute, and I didn't find anything about local statues either. So unless they have a warrant out for them, those people are going to walk free. (IANAL)

Also... cars don't use pins, so they wouldn't have been using a bump key for a car, but possibly a jiggler or a blank for impressioning.