The Legislature, a majority of the membership of each house concurring, may tax corporations, including state and national banks, and their franchises by any method not prohibited by this Constitution or the Constitution or laws of the United States.
Unless otherwise provided by the Legislature, the tax on state and national banks shall be according to or measured by their net income and shall be in lieu of all other taxes and license fees upon banks or their shares, except taxes upon real property and vehicle registration and license fees.
Cal. Const. art. XIII § 27