N.J. Stat. Ann. § 30:4-162

The State board shall establish geographic districts within the State, each consisting of one or more of the several counties, and shall designate the State hospital which shall receive persons admitted or committed from the several counties comprising each such district and shall notify the administrative director of the courts and the several county adjusters of the composition of such districts so that patients shall be received in the institution best suited to serve their needs with respect to proximity to their county of residence and availability of facilities in the State mental hospitals.