Mass. Gen. Laws ch. 112 § 80
Whoever, not being lawfully authorized to practice as a registered nurse within the commonwealth, practices or attempts to practice professional nursing or uses the abbreviation R.N., or any other words, letters or figures to indicate that the person using the same is such a registered nurse, shall, except as provided in section sixty-five, be punished by a fine of not more than five hundred dollars; provided, however, that a nonresident, licensed to practice professional nursing in another jurisdiction, may attend upon a nonresident of the commonwealth temporarily abiding here. Whoever becomes or attempts to become registered as a registered nurse or practices or attempts to practice professional nursing under a false or assumed name shall be punished by a fine of not less than five hundred nor more than one thousand dollars or imprisonment for one year, or both.
Mass. Gen. Laws ch. 112, § 80