Prostitute has a surprise for some Metro Vice officers

Mmmnn, I can think of a couple of ways - they gave the number to an informant, for example. Or they called someone while working a case and the number came up on caller ID. I know that many "official" cell phones come up "private" - but that in itself is a giveaway.

Why not just keep a bank of cell phones for plainclothes to use? I agree with another poster, unless you are truly undercover - and few LMPD officers really work undercover - they work plainclothes - there's a difference - true undercover officers do NOT make arrests - you are easy to find anyway.

How many cops have checked the phone book recently? One buddy of mine found a surprise, his "unlisted" number was suddenly listed - because his new wife didn't like being unlisted ....