Mich. Comp. Laws § 462.19: Civil liability.

Sec. 19.

If any common carrier shall do, or cause to be done, or permit to be done, any matter, act or thing in this act prohibited or declared to be unlawful, or shall omit to do any act, matter or thing required to be done by it, or by any lawful order made under the provisions of this act by the Michigan railroad commission, such common carrier shall be liable to the person, firm or corporation injured thereby in double the amount of damages sustained in consequence of such violation: Provided, That any recovery as is in this section provided shall in no manner affect a recovery by the state of the penalty prescribed for such violation.