But why would they?  It's not against the law for your phone number to be on another person's phone.  It proves no wrong-doing. Now, if a gal gets busted there is always a chance that you will get a call from LE. At that point you would simply exercise your right to STFU and say nothing.

The cops can look through her phone and very well may call you.  Remember: you have the right to remain silent. Do not talk to the cops because ANYTHING you say can and will be misquoted and used against you.  Stand your ground because your silence cannot be used against you in court. If the cops press you just say you do not wish to talk to them and terminate the conversation.  I would actually say "I elect to remain silent".  The government must prove your guilt beyond a reasonable doubt -- you do not have to prove your innocence.

Any phone can be tracked down.  Is it worth LE time Na.. Unless she is wanted for something bigger.. Ie.. NOt paying taxes, money laundering.. ect..

I reccomend paying cash for a Prepaidphone and refilling it when you hobby.

unless something really bad happen, I don't think LE would bother with tracking numbers down in it.  As one person said, I would use a seperate TracePhone, and different e-mail when speaking to providers. Also would be helpful to have different name when talking to providers.