N.J. Stat. § 40:23-6.53
The governing body of any county may enter into a contract with a private agency or firm for the purpose of collecting delinquent fees, fines, costs, surcharges, and other penalties or assessments imposed, after a final determination of guilt, by a central municipal court established pursuant to subsection e. of N.J.S. 2B:12-1, or imposed, after a final determination of guilt, on cases that were filed in a regional municipal court established pursuant to N.J.S. 2B:12-34. The use of private agencies or firms to collect delinquent fees, fines, costs, surcharges and other penalties or assessments imposed by a central municipal court or for cases filed in a regional municipal court shall be in accordance with rules or procedures adopted by the Supreme Court. Any such contract shall be made pursuant to the provisions of the "Local Public Contracts Law," P.L. 1971, c. 198 (C.40A:11-1 et seq.). The governing body of any county may authorize the assessment of a fee by a private agency or firm not to exceed 22% of the amount collected to be paid by the debtor to the private agency or firm to pay for the costs of collection.
N.J.S. § 40:23-6.53