N.J. Stat. § 30:9-12.12
No action at law shall lie or be maintained against any officer or employee or member of the board of managers for refusing to admit any person as a patient or for admitting, receiving, keeping, detaining, transferring or discharging any patient as provided by this act or as directed by any order made in accordance with this act, whether such person made his own application or the application was made by a friend or relative, or an order was made by a judge or court of the county or State, or any municipality thereof in any of which cases any such application or other, or certified copy thereof, shall be sufficient warrant and authority for the admission, keeping, detention, transfer, discharge and for the reasonable care, treatment, management and control of any patient received or committed under the terms of this act.
N.J.S. § 30:9-12.12