law: 18. Discharge of voluntary patients.-
  (1) The medical officer in charge of a psychiatric hospital or psychiatric nursing home shall, on a request made in that behalf,-
  (a) by any voluntary patient; and
  (b) by the guardian of the patient, if he is a minor voluntary patient, discharge, subject to the provisions of sub-section (3) and within twenty-four hours of the receipt of such request, the patient from the psychiatric hospital or psychiatric nursing home.
  (2) Where a minor voluntary patient who is admitted as an inpatient in any psychiatric hospital or psychiatric nursing home attains majority, the medical officer in charge of such hospital or nursing home shall, as soon as may be, intimate the patient that he has attained majority and that unless a request for his continuance as an inpatient is made by him within a period of one month of such intimation, he shall be discharged, and if, before the expiry of the said period, not request is made to the medical officer in charge for his continuance as an inpatient, he shall, subject to the provisions of sub-section (3), be discharged on the expiry of the said period.
  (3) Notwithstanding anything contained in sub-section (1) or sub-section (2), where the medical officer-in-charge of a psychiatric hospital or psychiatric nursing home is satisfied that the discharge of a voluntary patient under sub-section (1) or sub-section (2) will not be in the interest of such voluntary patient, he shall, within seventy-two hours of the receipt of a request under sub-section (1), or, if no request under sub-section (2) has been made by the voluntary patient before the expiry of the period mentioned in that sub-section, within seventy-two hours of such expiry constitute a Board consisting of two medical officers and seek its opinion as to whether such voluntary patient needs further treatment and if the Board is of the opinion that such voluntary patient needs further treatment in the psychiatric hospital or psychiatric nursing home, the medical officer shall not discharge the voluntary patient, but continue his treatment for a period not exceeding ninety days at a time.