Expected to testify is Benjamin David Rettig, 25, who took a plea deal and was sentenced in December 2011 to spend at least 25 years in prison for holding Mortensen at gunpoint while Bond allegedly slit the man's throat.
According to court documents, Bond and Rettig broke into the retired BYU professor's Payson Canyon home in 2009 to steal an extensive weapons collection. Both men were in need of money and Bond, whose father was a friend of Mortensen's, knew of the weapons, according to testimony.
Wearing ski masks and latex gloves, Rettig held Mortensen at gunpoint while Bond collected the firearms from a bunker behind the home, according to prosecutors.
The men then forced Mortensen into an upstairs bathroom. With Rettig's gun still trained on Mortensen, Bond slashed the professor's throat, prosecutors allege.
Shortly after the slaying, Mortensen's son and daughter-in-law, Roger and Pamela Mortensen, knocked on the door to deliver a pecan pie.
Pamela Mortensen testified during Bond's preliminary hearing that Bond pulled out a handgun, and with Rettig's help, used zip ties to bind the couple's hands.
The men asked for their cellphones and IDs, Pamela Mortensen said, and told the couple that they would live, but only if they told police the robbery had been committed by three black men.
Police later arrested Roger and Pamela Mortensen in connection with the slaying. The couple spent five months in jail before Bond's ex-wife, Rachel Bingham, tipped police to Bond and Rettig, who were living in Vernal.
According to police, Bingham told them that Bond confessed to her that he had a role in the killing, and asked her to help him dispose of some of the weapons. Bingham pointed investigators to Vernal, where detectives recovered at least 14 of Mortensen's weapons from a site where the two men buried them on the night of the slaying, prosecutors said.
Rettig pleaded guilty in June 2011 to aggravated murder and aggravated kidnapping. In exchange, prosecutors agreed to not seek the death penalty and to drop charges of aggravated kidnapping and aggravated burglary. As part of the plea deal, Rettig also agreed to testify against Bond.
The death penalty has also been taken off the table for Bond, after a partial resolution was reached in November. If found guilty of aggravated murder, Bond will be sentenced to life without the possibility of parole.