"Civil matter with criminal consequences"?? That's a hilarious contradiction! And it's proof that the idiot harassing you has no idea what he or she is talking about. It's just scam aimed at scaring you into handing over your money to them. First of all, no debt collector has the authority to have you arrested or criminally charged. And it's illegal for them to imply such a thing!
If I were you, I'd find an attorney in my area affiliated with the National Association of Consumer Advocates (
www.naca.net ) and gleefully pursue every avenue of punishment -- both criminal and civil -- against this criminal debt collector for violating the Fair Debt Collection Practices Act.
If you don't want to go that route, you could always send them a certified letter directing them to cease communication with you. After receiving such a notice, the collector can legally contact you just on more time. Then after that, the collector can never legally contact you again. Here are a couple sample letters that you could adapt to your situation:
http://www.budhibbs.com/cease_comm.htm or
http://credit.about.com/od/debtcollection/a/ceaseanddesist.htm Just be sure to send the letter via certified US Mail.
Also, you can easily report this criminal debt collector's illegal behavior to the Federal Trade Commission here:
http://ftc.gov/ftc/cmplanding.shtmRemember: all the threats of criminal charges, etc. are not only untrue, they're illegal. So relax and put the screws to these criminals. Good luck!