N.J. Stat. § 34:15-137
Nothing in this act shall affect any existing contract or policy of employers' liability insurance or the liability of any insurance company or provider, or any arrangement now existing between employers and employees, providing for the payment to such employees, their families, dependents or representatives of sick, accident or death benefits in addition to the workers' compensation coverage provided pursuant to this act; but the liability for such compensation shall not be reduced or affected by any insurance, contribution or other benefit whatsoever, due to or received by the person entitled to such compensation, and the person so entitled shall, irrespective of any such insurance or other contract, have the right to recover the compensation directly from the employer under an existing contract or policy of employers' liability insurance. The board shall have the same rights provided other employers under R.S. 34:15-40.
N.J.S. § 34:15-137