N.J. Stat. § 30:4-27.20
A voluntary patient at a short-term care or psychiatric facility or special psychiatric hospital shall be discharged by the treatment team at the patient's request. The treatment team shall document all requests for discharge, whether oral or written, in the patient's clinical record. The facility shall discharge the patient as soon as possible but in every case within 48 hours or at the end of the next working day from the time of the request, whichever is longer, except that if the treatment team determines that the patient needs involuntary commitment, the treatment team shall initiate court proceedings pursuant to section 10 of this act. The facility shall detain the patient beyond 48 hours or the end of the next working day from the time of the request for discharge, only if the court has issued a temporary court order.
N.J.S. § 30:4-27.20