California Code, Elections Code - ELEC § 3021.5

(1) Authorization for a vote by mail ballot and accompanying voting materials to be sent to an out-of-state emergency worker by mail, facsimile transmission, or electronic transmission, as requested by the out-of-state emergency worker. An elections official may use reasonable facsimiles of the county voter information guides sent to voters as vote by mail ballots.

(2) A requirement that an out-of-state emergency worker mark the vote by mail ballot provided to them, place it in the vote by mail ballot identification envelope, and return the vote by mail ballot to the elections official from whom it was obtained. If no identification envelope is provided, the envelope used to return the vote by mail ballot to the elections official shall include the information required by subdivision (a) of Section 3011 and a statement signed under penalty of perjury that the voter is an out-of-state emergency worker.