Hello m:

It's not nice to snitch.

excon

To report a parolee for violating his parole, you can call the police (if it's a violence issue or crime) or the board of parole (or probation depending on jurisdiction). You can call the courthouse, they should be able to direct you from there.

What is your definition of "problem parolee?" Violation of the terms of probation? Something else?

In my area you would call the State Parole Board. I do agree with Excon. What is your interest in this? The vast majority of these posts are from people who "simply" want to cause a problem for someone else.

Same with immigration questions.

What are they doing, if they are breaking a law, call the police, if they are breaking some other term of probation, contact the local probation office