N.J. Stat. § 40:20-82
Whenever the board of chosen freeholders shall have appointed a committee of its members upon any matter within its jurisdiction, or to examine any officer of said board, or holding an appointment from said board in relation to the discharge of his official duties or conduct, or to the receipt or disbursement by him of any moneys in the discharge of said duties, or concerning the possession or disposal by him, in his official capacity of any property belonging to said board or to the county, or to inspect or examine any book, account, voucher or document in the possession or under the control of such officer, relating to the affairs or interest of said county, the chairman of the committee, or any member thereof, may administer an oath to any person attending as a witness before that committee.
N.J.S. § 40:20-82