(1) To ensure the election administrator has information sufficient to determine the elector's eligibility to vote, an elector voting by mail may enclose in the outer signature envelope, together with the voted ballot in the secrecy envelope:
(a) a Montana driver's license number, Montana state identification card number issued pursuant to 61-12-501, or the last four digits of the applicant's social security number;
(b) a readable copy of a military identification card, a tribal photo identification card, a United States passport, a Montana concealed carry permit, or a student photo identification card issued by the Montana university system or a school that is a member of the national association of intercollegiate athletics; or
(c) (i) any other form of readable photo identification with the elector's name; and
(ii) a copy of a current utility bill, bank statement, paycheck, notice of confirmation of voter registration issued pursuant to 13-2-207, government check, or other government document that shows the elector's name and current address.
(2) The elector's ballot must be handled as a provisional ballot under 13-15-107 if:
(a) a provisionally registered elector voting by mail does not enclose with the ballot the information described in subsection (1);
(b) the information provided under subsection (1) is invalid or insufficient to verify the elector's eligibility; or
(c) the elector's name does not appear on the precinct register.