Cal. Probate Code § 3208

(a) Except as provided in subdivision (b), the court may make an order authorizing the recommended health care for the patient and designating a person to give consent to the recommended health care on behalf of the patient if the court determines from the evidence all of the following: (1) The existing or continuing condition of the patient’s health requires the recommended health care. (2) If untreated, there is a probability that the condition will become life-endangering or result in a serious threat to the physical or mental health of the patient. (3) The patient is unable to consent to the recommended health care. (b) In determining whether the patient’s mental functioning is so severely impaired that the patient lacks the capacity to make any health care decision, the court may take into consideration the frequency, severity, and duration of periods of impairment. (c) The court may make an order authorizing withholding or withdrawing artificial nutrition and hydration and all other forms of health care and designating a person to give or withhold consent to the recommended health care on behalf of the patient if the court determines from the evidence all of the following: (1) The recommended health care is in accordance with the patient’s best interest, taking into consideration the patient’s personal values to the extent known to the petitioner. (2) The patient is unable to consent to the recommended health care.