N.J. Stat. § 30:8-23: Rules and regulations; punishments.

When the board of chosen freeholders of any county shall have assumed the custody, rule, keeping and charge of the county jail of such county pursuant to section 30:8-19 of this title, such board shall prescribe rules and regulations for the management and conduct of such jail, and the employment, maintenance and keeping of the prisoners therein, and may authorize and require the keeper or warden of such jail to enforce such rules and regulations, and to punish any breach of the same by the prisoners, and any refusal to work, or any insubordination, by solitary confinement, change or diminution of food and diet, or such other reasonable punishments as they may prescribe.