California Code, Penal Code - PEN § 971

The distinction between an accessory before the fact and a principal, and between principals in the first and second degree is abrogated;  and all persons concerned in the commission of a crime, who by the operation of other provisions of this code are principals therein, shall hereafter be prosecuted, tried and punished as principals and no other facts need be alleged in any accusatory pleading against any such person than are required in an accusatory pleading against a principal.