CA Prob Code Section 3201

(a)

A petition may be filed to determine that a patient has the capacity to make a health care decision concerning an existing or continuing condition.

(b)

A petition may be filed to determine that a patient lacks the capacity to make a health care decision concerning specified treatment for an existing or continuing condition, and further for an order authorizing a designated person to make a health care decision on behalf of the patient.

(c)

One proceeding may be brought under this part under both subdivisions (a) and (b).