For the purpose of having a judicial determination of the date of birth, any citizen of the United States, either natural born or naturalized, may file a petition with the clerk of the district court of the county of the citizen's residence.
Mont. Code Ann. § 27-32-101
Who may petition -- where petition filed
En
Official source: Montana Code Annotated (Montana Legislature). Reproduced from public-domain Montana statutes; confirm against the official source for the current text. Not legal advice.