Mont. Code Ann. § 32-2-952

Any photostatic, photographic, or microfilm reproductions, including enlargements, of any original records or files of a mutual association, whether in the form of an entry or entries in a book or any other form of record, are admissible in evidence in any court of competent jurisdiction in proof of an act, transaction, occurrence, or event if shown to be made in the regular course of business of the mutual association. Nothing in 32-2-950 through 32-2-954 may be construed to authorize the use of secondary evidence in administrative or court proceedings if original records are in existence and available for use in accord with the rules of evidence.