N.J. Stat. § 43:22-1
In order to extend to certain persons holding office, position or employment in the service of the State and of any county, municipality or school district and of any public department, board, body, commission, institution, agency, instrumentality or authority of, or in, the State and of, or in, any county, municipality or school district in the State and to the dependents and survivors of such persons, the basic protection accorded to others by the old-age and survivors insurance system embodied in the Federal Social Security Act, it is hereby declared to be the public policy of this State, subject to the limitations of this act, that such steps be taken as to provide such protection to such persons, on as broad a basis as is permitted under the Social Security Act.
Nothing contained in this act shall in any way impair the protection afforded employees in positions covered by a retirement system on the date an agreement under this act is made applicable to service performed in such positions, or receiving periodic benefits under such retirement system at such time.
N.J.S. § 43:22-1