It shall be unlawful for any common carrier, subject to the provisions of this act, to make or give any undue or unreasonable preference or advantage to any particular person, company, firm, corporation or locality or any particular description of traffic in any respect whatsoever, or to subject any particular person, company, firm, corporation or locality or any particular description of traffic to any undue or unreasonable disadvantage or prejudice in any respect whatsoever.
MCL 462.17