Mass. Gen. Laws ch. 112 § 9E
Notwithstanding any other provisions of law, a physician assistant may perform medical services when such services are rendered under the supervision of a registered physician. Such supervision shall be continuous but shall not require the personal presence of the supervising physician or physicians.
Physician assistants, depending upon their level of professional training and experience as determined by a supervising physician, may perform medical services of a general nature and may order tests and therapeutics in assisting physicians in private practice, in group practices or in health care facilities, consistent with any applicable bylaws and policies of such facilities.
A physician assistant may order therapeutics and tests and issue written prescriptions for patients subject to the provisions of paragraph (g) of section seven of chapter ninety-four C.
If a physician assistant is employed by a physician or group of physicians, the assistant shall be supervised by and shall be the legal responsibility of the employing physician or physicians. The legal responsibility of such assistant shall remain that of the employing physician or physicians at all times including occasions when the assistant, under the direction and supervision of the employing physician or physicians, aids in the care and treatment of patients in health care facilities.
If a physician assistant is employed by a health care facility, the legal responsibility for his actions and omissions shall be that of the employing facility. Such physician assistants shall be supervised by registered physicians. Such physician assistants employed by health care facilities shall not be utilized as the sole medical personnel in charge of emergency or outpatient services or any other clinical service where a physician is not regularly available.
Notwithstanding any other provisions of law, a physician assistant trainee may perform medical services when such services are rendered within the scope of a program approved under section nine K.
Mass. Gen. Laws ch. 112, § 9E