HELENA, Mont. -

The Montana Supreme Court has upheld a lower court ruling granting a new trial to a man charged in the July 2005 beating death of a former chairman of the Confederated Salish and Kootenai Tribe.
    
Clifford Oldhorn was convicted of deliberate homicide in the death of 73-year-old Harold Mitchell Jr., and sentenced to 100 years in prison. He appealed, arguing statements he made to investigators shouldn't have been used against him because he believed he had immunity.
    
The Montana Supreme Court said a letter from Lake County Attorney Mitch Young explaining the immunity agreement contained legal distinctions that are "not readily apparent even to those trained in the law," and that statements made by officers led Oldhorn to believe he would not be prosecuted.
    
Prosecutors have said without Oldhorn's statements they likely couldn't gain a conviction.