Mont. Code Ann. § 25-13-308
25-13-308 Execution against person of judgment debtor
25-13-308 . Execution against person of judgment debtor. If the writ is against the person of the judgment debtor, it must require the sheriff to arrest the debtor and commit the debtor to the jail of the county until the debtor pays the judgment, with interest, or is discharged, according to law.