N.J. Stat. Ann. § 40:43-17

If the newly created municipality includes a portion of any other municipality, the governing body of the newly created municipality shall forthwith appoint from among its members a committee of three, and a like committee shall be appointed by the governing bodies of each of the municipalities a portion of which has been included in the newly created municipality. The committees together shall be termed a joint committee, but no such joint committee shall function in case any of the municipalities shall proceed to have commissioners appointed under the provisions of section 40:43-21 of this title.