BILLINGS, Mont. -

Attorneys for a Colorado man accused of murdering a teacher in Montana's oil patch want his accomplice to appear as a defense witness when the case goes to trial.
    
Twenty-five-year-old Michael Keith Spell could face life in prison if convicted in the 2012 killing of 43-year-old Sherry Arnold.
    
His accomplice, Lester Van Waters, Jr., pleaded guilty last year to deliberate homicide by accountability in a deal with prosecutors sparing him the death penalty.
    
Spell's attorneys said in documents filed Friday that statements by Waters during his plea hearing show Spell did not intend to injure Arnold.
    
Prosecutors say Spell grabbed Arnold while she was jogging and choked or otherwise asphyxiated the Sidney High School math teacher.
    
Her body was found more than two months later in neighboring North Dakota.