Cal. Gov. Code § 17513

“Costs mandated by the federal government” means any increased costs incurred by a local agency or school district after January 1, 1973, in order to comply with the requirements of a federal statute or regulation. “Costs mandated by the federal government” includes costs resulting from enactment of a state law or regulation where failure to enact that law or regulation to meet specific federal program or service requirements imposed upon the state would result in substantial monetary penalties or loss of funds to public or private persons in the state whether the federal law was enacted before or after the enactment of the state law, regulation, or executive order. “Costs mandated by the federal government” does not include costs which are specifically reimbursed or funded by the federal or state government or programs or services which may be implemented at the option of the state, local agency, or school district.