California
Probate Code – PROB § 4503
(1) The power of attorney is executed by the principal at a time when the principal has the advice of a lawyer authorized to practice law in the state where the power of attorney is executed.
(2) The principal’s lawyer signs a certificate stating in substance:
“I am a lawyer authorized to practice law in the state where this power of attorney was executed, and the principal was my client at the time this power of attorney was executed. I have advised my client concerning his or her rights in connection with this power of attorney and the applicable law and the consequences of signing or not signing this power of attorney, and my client, after being so advised, has executed this power of attorney.”
(b) A power of attorney may not limit the authority of the attorney-in-fact, the principal, the conservator of the person or estate of the principal, or the public guardian to petition under this part.