Mass. Gen. Laws ch. 149 § 148A
No employee shall be penalized by an employer in any way as a result of any action on the part of an employee to seek his or her rights under the wages and hours provisions of this chapter.
Any employer who discharges or in any other manner discriminates against any employee because such employee has made a complaint to the attorney general or any other person, or assists the attorney general in any investigation under this chapter, or has instituted, or caused to be instituted any proceeding under or related to this chapter, or has testified or is about to testify in any such proceedings, shall have violated this section and shall be punished or shall be subject to a civil citation or order as provided in section 27C.
Mass. Gen. Laws ch. 149, § 148A