N.J. Stat. Ann. § 53:5A-14.2

2. The adjustment in survivors' benefits pursuant to this act, P.L.2001, c.350, shall apply to benefit entitlements granted prior to and in effect on the effective date of this act but only for benefit payments after the effective date of this act. No surviving spouse or surviving child of a deceased member of the retirement system shall be granted a retroactive payment based upon the difference between the benefit the person would have received if the adjustment pursuant to this act had been applicable at the date of entitlement and the benefit that the surviving spouse or surviving child has received from the date of entitlement to the effective date of this act.