Mass. Gen. Laws ch. 152 § 37
Whenever an employee who has a known physical impairment which is due to any previous accident, disease or any congenital condition and is, or is likely to be, a hindrance or obstacle to his employment, and who, in the course of and arising out of his employment, receives a personal injury for which compensation is required by this chapter and which results in a disability that is substantially greater by reason of the combined effects of such impairment and subsequent personal injury than that disability which would have resulted from the subsequent personal injury alone, the insurer or self-insurer shall pay all compensation provided by this chapter. If said subsequent injury is caused by the preexisting impairment or if said subsequent personal injury of such an employee shall result in the death of the employee, and it shall be determined that the death would not have occurred except for such pre-existing physical impairment, the insurer shall pay all compensation provided by this chapter.
Insurers making payments under this section shall be reimbursed by the state treasurer from the trust fund created by section sixty-five in an amount not to exceed seventy-five percent of all compensation due under sections thirty-one, thirty-two, thirty-three, thirty-four A, thirty-six A, and, where benefits are due under any of such sections, section thirty; provided, however, that the insurer is not a self-insurer, a group self-insurer or municipality that has chosen not to be subject to the assessments which fund said reimbursements; and, provided, further, that no reimbursement shall be made for any amounts paid during the first one hundred and four weeks from the onset of disability or death.
There shall be no reimbursement under this section unless the employer had personal knowledge of the existence of such pre-existing physical impairment within thirty days of the date of employment or retention of the employee by such employer from either a physical examination, employment application questionnaire, or statement from the employee. Proof of the pre-existence of such impairment shall be established only by the production of medical records existing prior to the date of employment or retention in employment of the employee. Nothing in this paragraph shall be construed to allow employers to compel an employee or job applicant to disclose any information regarding physical impairments in violation of any applicable law.
The office of legal counsel shall in all instances have the authority to defend claims against the fund. Such office shall have the right to contest any amount accredited to the above named sections which has been redeemed by an insurer by payment of a lump sum settlement pursuant to section forty-eight, but reimbursement shall not require the approval of the lump sum by said office or by the state treasurer. No reimbursement shall be made for payments due during the first one hundred and four weeks from the date of onset of disability or death, whether paid under an agreement, decision, or lump sum settlement. Any petition for reimbursement under this section shall be filed no later than two years from the date on which the benefit payment for which the reimbursement request is being filed was made.
Mass. Gen. Laws ch. 152, § 37