Looks like you asked it under a different thread and answerd here.
http://www.expertlaw.com/forums/showthread.php?t=119753
Keep in mind to prove false information in their affadavitt is an expensive and difficult process if you go hire a lawyer yourself, unless the state AG can come in and subpoena their records, prove a pattern of behavoir, and prove a signle person served several hundred summons a day, which is impossible. Your best bet is file a complaint with the AG's office.
I handle payrolls, and when a writ of garnishment is served, it is up to the employee to take legal action to stop it. There's nothing an employer can do. On the other hand, if you really owe the money, you'll have to decide if you want to drag it out, or see if you can get this over and done with.

