(a) A county clerk, district clerk, or other public official on request shall furnish without cost to a person or the person's guardian, dependent, or heir one or more certified copies of a document that is in the custody of or on file in the county clerk's, district clerk's, or other public official's office if:
(1) the person or the person's guardian, dependent, or heir is eligible to make a claim against the United States government because of service in the United States armed forces or an auxiliary service, including the maritime service or the merchant marine; and
(2) the document is necessary to prove the claim.
(b) The issuance of a certified copy under this section may not be considered in determining the maximum fee of the office.