California Code, Financial Code - FIN § 40501

In accordance with the implied contract existing between a financial institution and its depositor, no bank, savings association, credit union, or other financial institution operating in this state which maintains and services demand deposit accounts, including NOW accounts, may release any funds from those accounts to any person or entity who is not the account holder, unless the funds are released pursuant to the depositor's authorization or in accordance with the law.  This section does not apply to any setoff for a debt claimed to be owed to a bank, savings association, credit union, or other financial institution by a customer.