N.J. Stat. § 43:10-18
Any independent pension fund group, composed of state, county or city employees, in any county of the first class, may, by a vote of at least two-thirds majority of its members, make application to the county employees' pension commission of that county for leave to become part and parcel of the county employees' pension fund and to receive the benefits therefrom.
Such county employees' pension commission by agreement of a majority of its members, may accept such application, whereupon the board of chosen freeholders which is the custodian or treasurer of the independent pension group shall turn over to the county treasurer, the custodian of the funds of the county employees' commission, all of the funds of the independent pension group, which in every respect shall become a part of the common fund of the county employees' pension commission.
Each member of an independent pension group which is accepted by the county employees' pension fund shall have and enjoy all of the rights of seniority and all other rights and privileges provided by article 1 of chapter 10 of this title (s. 43:10-1 et seq.).
N.J.S. § 43:10-18