N.J. Stat. Ann. § 48:3-4

No public utility shall make or give, directly or indirectly, any undue or unreasonable preference or advantage to any person, locality or particular description of traffic, or subject any particular person, locality or particular description of traffic to any prejudice or disadvantage. Notwithstanding the provisions of section 48:3-1 of the Revised Statutes and this section a public utility engaged in the distribution and sale of gas and electricity or either thereof may supply such services to its employees at reduced rates.