SIDNEY – A Colorado man has pleaded guilty to the 2012 murder of a Montana teacher in an oil boom town where residents say their lives were forever altered by the crime.
Montana District Judge Richard Simonton on Wednesday accepted the guilty plea from Michael Keith Spell on a count of deliberate homicide. A charge of attempted kidnapping was dropped under a plea agreement.
Prosecutors are recommending a 100-year sentence. They want Spell to serve his time in prison.
Attorneys for Spell want the mentally disabled 25-year-old from Parachute, Colorado, committed to a state institution for the disabled.
Spell admitted to killing Sherry Arnold during an attempted abduction as the 43-year-old Sidney High School math teacher was out for a pre-dawn jog. An accomplice pleaded guilty last year and is awaiting sentencing.
Richland County prosecutor Mike Weber said he would oppose any sentence short of prison for the Parachute, Colorado, man.
“We’ll be arguing for Montana State Prison. That’s our position,” Weber said.
Avignone, however, said he will ask that Spell be sentenced to the state health department, which could allow him to serve his time in a facility for the mentally disabled. The defense also reserved the right to ask for a lesser sentence.
“He’s going to be intellectually disabled until the day he dies,” Avignone said. “But that doesn’t mean he can’t learn and he can’t learn life skills.”
Experts for the state and defense have testified that Spell is mildly mentally disabled. He can barely read or write and has a history of low IQ scores. Those findings prompted prosecutors to drop their pursuit of the death penalty.
Arnold, a mother of two and a popular teacher in close-knit Sidney, was killed just blocks from her house after going out for jog on Jan. 7, 2012.
Her body was found more than two months later in a shallow grave in a once-quiet part of North Dakota that over the past decade has become the center of one of the country’s largest oil booms.
Accomplice Lester Van Waters pleaded guilty last year to deliberate homicide by accountability in a deal that called for him to testify against Spell if the case went to trial. Waters in turn would be spared the death penalty and receive 100 years in prison.
He has not yet been sentenced.
Court documents say Spell and Waters traveled to Sidney from Colorado, using crack cocaine throughout the trip. They told friends and family they were searching for work in the Bakken oil fields along the Montana-North Dakota border.
Authorities have said Spell choked or otherwise asphyxiated Arnold during an attempted abduction.
Spell’s attorneys did not dispute that he was involved in the events leading to Arnold’s death. Yet they maintained there was no conclusive evidence he was the one who killed her.