California Code, Welfare and Institutions Code - WIC § 21000

(a) Adults with disabilities, including older adults with disabilities, are presumed competent and to have the capacity to make decisions regarding their day-to-day health, safety, welfare, and social and financial affairs, unless otherwise determined through legal proceedings.

(b) All adults, to the best of their ability and with supports they choose, should be able to be informed about, and participate in, the management of their affairs.

(c) Like adults without disabilities, adults with disabilities may use a wide range of voluntary supports to help them understand, make, and communicate their own decisions.  These voluntary arrangements should be encouraged and recognized as a valid way for people with disabilities to strengthen their capacity and maintain their autonomy.

(d) The capacity of an adult should be assessed with any supports, including supported decisionmaking, that the person is using or could use.

(e) Supported decisionmaking offers adults with disabilities a flexible way to maintain autonomy and decisionmaking authority over their own lives by developing and maintaining voluntary supports to assist them in understanding, making, communicating, and implementing their own informed choices.

(f) Supported decisionmaking can be a way to strengthen the capacity of an adult with a disability.

(g) Supported decisionmaking is one of several options available to adults with disabilities to understand, make, and communicate decisions and to express preferences, including, but not limited to, medical and financial powers of attorney, authorized representative forms, health care directives, release of information forms, and representative payees.