Christopher Todd Johnson, 50, pleaded guilty to the Class C felony of voluntary manslaughter on Friday afternoon. Johnson had originally been charged with first-degree murder, a Class A felony, for the 2016 homicide of 51-year-old Donald Preston.

During a plea hearing on Friday, Johnson admitted to shooting Preston twice on Dec. 20, 2016, and claimed he was provoked.

“On that date, Don Preston attacked me physically,” Johnson said. “In response, I shot him once, then he was no longer a threat to my safety. Shortly after that, I shot him again and he died. I acted solely out of a sudden, irresistible passion resulting from a serious provocation.”

Chief District Court Judge Adria Kester accepted Johnson’s guilty plea.

A sentencing hearing is scheduled for March 22. Voluntary manslaughter is a forcible felony, meaning he cannot receive a suspended prison sentence or deferred judgment. Class C felonies carry an indeterminate sentence of up to 10 years in prison and because of a dangerous weapon enhancement added to the charge, Johnson will have to serve a mandatory five years of that term. He will also have to pay a fine between $1,000 and $10,000 and pay $150,000 in victim restitution to Preston’s next of kin.

Johnson was arrested and charged with Preston’s death on Feb. 2, 2023 — more than six years after Preston’s body was found by a farmer near Moorland on Dec. 26, 2016. He had been a person of interest in Preston’s death since 2017, but Johnson was already facing time in federal prison, so investigators decided to hold off on charging him until his federal sentence was complete.

Shortly after Preston’s body was found, the Iowa Division of Criminal Investigation and the Webster County Sheriff’s Office began a joint investigation into the death. An autopsy two days later concluded that Preston had died of gunshot wounds to the head and abdomen and the death was ruled a homicide. At the scene, investigators found three unspent .40-caliber rounds and six spent .40-caliber ammunition casings.

In a search warrant filed during the investigation, DCI Special Agent Scot Ely stated that Preston was last seen alive on Dec. 20, 2016, leaving a residence in Fort Dodge with Johnson in Johnson’s car.

Preston’s last cell phone activity was around 4:30 p.m. on that day.

“Although Preston’s body was not found until Dec. 26, there is no indication Preston was alive after Dec. 20 when he was with Johnson,” Ely wrote in an October 2017 search warrant for Johnson’s cell phone records. “The matched shell casings indicate that Christopher Johnson’s .40 Glock was used to kill Donald Preston.”