An offender convicted of having committed attempted deliberate homicide, aggravated assault, or aggravated kidnapping while in official detention, as defined in 45-2-101, shall, if the provisions of 46-1-401 have been complied with, be sentenced to death or life imprisonment as provided in 46-18-301 through 46-18-310.
Sentences For Certain Offenses Committed In Official Detention -- Death Penalty
Mont. Code Ann. § 46-18-220, under Form of Sentence.
Mont. Code Ann. § 46-18-220