N.J. Stat. Ann. § 2A:16-8

Whenever any judgment is recovered in an action in any court of competent jurisdiction in this state, against any municipality by any person who is, at the time of the recovery of the judgment, indebted to such municipality upon any indebtedness of a public nature, including taxes, assessments or water rates which constitute an indebtedness, or who shall become so indebted before the satisfaction of the judgment, such municipality may apply to the court in the action for an order to reduce or extinguish the judgment, and any execution issued thereon, by offsetting and crediting against the same any such indebtedness.