The following words as used in this section shall have the following meanings:
"Patient", a person who, during the course of diagnosis or treatment, communicates with a psychotherapist;
"Psychotherapist", a person licensed to practice medicine, who devotes a substantial portion of his time to the practice of psychiatry. "Psychotherapist" shall also include a person who is licensed as a psychologist by the board of registration of psychologists or a person who is a registered nurse licensed by the board of registration in nursing whose certificate of registration has been endorsed authorizing the practice of professional nursing in an expanded role as a psychiatric nurse mental health clinical specialist, pursuant to the provisions of section eighty B of chapter one hundred and twelve.
"Communications" includes conversations, correspondence, actions and occurrences relating to diagnosis or treatment before, during or after institutionalization, regardless of the patient's awareness of such conversations, correspondence, actions and occurrences, and any records, memoranda or notes of the foregoing.
Except as hereinafter provided, in any court proceeding and in any proceeding preliminary thereto and in legislative and administrative proceedings, a patient shall have the privilege of refusing to disclose, and of preventing a witness from disclosing, any communication, wherever made, between said patient and a psychotherapist relative to the diagnosis or treatment of the patient's mental or emotional condition. This privilege shall apply to patients engaged with a psychotherapist in marital therapy, family therapy, or consultation in contemplation of such therapy.
If a patient is incompetent to exercise or waive such privilege, a guardian shall be appointed to act in his behalf under this section. A previously appointed guardian shall be authorized to so act.
Upon the exercise of the privilege granted by this section, the judge or presiding officer shall instruct the jury that no adverse inference may be drawn therefrom.
The privilege granted hereunder shall not apply to any of the following communications:
The provision of information acquired by a psychotherapist relative to the diagnosis or treatment of a patient's emotional condition, to any insurance company, nonprofit hospital service corporation, medical service corporation, or health maintenance organization, or to a board established pursuant to section twelve of chapter one hundred and seventy-six B, pertaining to the administration or provision of benefits, including utilization review or peer review, for expenses arising from the out-patient diagnosis or treatment, or both, of mental or nervous conditions, shall not constitute a waiver or breach of any right to which said patient is otherwise entitled under this section and section thirty-six B of chapter one hundred and twenty-three.
Mass. Gen. Laws ch. 233, § 20B