Mass. Gen. Laws ch. 176B § 4T
Any subscription certificate under an individual or group medical service agreement delivered, issued or renewed in the commonwealth shall provide as benefits to all individual subscribers and members within the commonwealth and to all group members having a principal place of employment within the commonwealth for services rendered by a certified registered nurse anesthetist or nurse practioner designated as such a certified registered nurse anesthetist or nurse practioner by the board of registration in nursing pursuant to the provisions of section 80B of chapter 112; provided, however, that the following conditions are met: (1) the service rendered is within the scope of the certified registered nurse anesthetist's license or nurse practioner's authorization to practice by the board of registration in nursing; and (2) the policy or contract currently provides benefits for identical services rendered by a provider of health care licensed by the commonwealth.
Mass. Gen. Laws ch. 176B, § 4T