New Jersey Statutes Title 48. Public Utilities 48 § 2-36

No person shall be excused from testifying or from producing any book, document or paper in any investigation or inquiry by or upon a hearing before the board or any member thereof when ordered so to do by the board or member, upon the ground that the testimony or documentary evidence required of him may tend to incriminate him or subject him to penalty or forfeiture, but no person shall be prosecuted, punished or subjected to any penalty or forfeiture on account of any matter or thing concerning which he shall, under oath, have testified or produced documentary evidence, except that he shall not be exempt from prosecution or punishment for any perjury committed by him in his testimony. Nothing herein shall give to any corporation immunity of any kind.