Section 813 Of Part 17. Legal Mental Capacity From California Probate Code >> Division 2. >> Part 17.

. (a) For purposes of a judicial determination, a person has the capacity to give informed consent to a proposed medical treatment if the person is able to do all of the following:
  (1) Respond knowingly and intelligently to queries about that medical treatment.
  (2) Participate in that treatment decision by means of a rational thought process.
  (3) Understand all of the following items of minimum basic medical treatment information with respect to that treatment:
  (A) The nature and seriousness of the illness, disorder, or defect that the person has.
  (B) The nature of the medical treatment that is being recommended by the person's health care providers.
  (C) The probable degree and duration of any benefits and risks of any medical intervention that is being recommended by the person's health care providers, and the consequences of lack of treatment.
  (D) The nature, risks, and benefits of any reasonable alternatives.
  (b) A person who has the capacity to give informed consent to a proposed medical treatment also has the capacity to refuse consent to that treatment.