Notwithstanding any other provision of law, if the state or any of its officials fail to defend the constitutionality of this act, following its approval by the voters, any other government agency of this state shall have the authority to intervene in any court action challenging the constitutionality of this act for the purpose of defending its constitutionality, whether that action is in state or federal trial court, on appeal, or on discretionary review by the Supreme Court of California or the Supreme Court of the United States. The reasonable fees and costs of defending the action shall be a charge on funds appropriated to the Department of Justice, which shall be satisfied promptly.