N.J. Stat. Ann. § 40A:10-5

The operator against whom a claim or demand is made or an action instituted, arising out of the operation or use of any motor vehicle, equipment or apparatus to which this article relates, shall promptly give written notice thereof to the governing body of the local unit. If an action is instituted against him he shall also move promptly as a third party plaintiff to name the local unit as third party defendant in that action. If the operator fails to so notify the local unit or name the local unit as a third party defendant in any such action, the local unit shall not be liable for any judgment recovered against him even though it failed to secure the insurance required by this article.