In a sudden about-face, a 33-year-old man agreed to plead guilty to fatally shooting a resident who came outside his home near Rochester with a gun to see what was going on.

William I. Shillingford, of nearby Kasson, entered his plea of guilt late Wednesday afternoon to second-degree unintentional murder in connection with the killing on May 8, 2022, of John L. Colbert just east of Byron, Minn., outside a home in the 5700 block of County Road 105.

The plea deal between the prosecution and the defense came on the day Shillingford's murder trial was about to start. The agreement calls for him to receive a sentence of 21¾ years. With credit for time in jail since his arrest, he is expected to serve roughly 13½ years in prison and the balance on supervised release.

In the meantime, Shillingford remains jailed without bail ahead of sentencing, which is scheduled for Jan. 8.

Olmsted County Chief Sheriff's Deputy Terry Waletzki told the Star Tribune after charges were filed that Shillingford and Colbert were acquaintances, and that the families knew each other. Waletzki added that Shillingford had hunted on Colbert's property in the past.

According to the criminal complaint and the Olmsted County Sheriff's Office:

David Colbert told a sheriff's deputy that a pickup truck pulled into the drive after dark and his father, John Colbert, "went outside to investigate," the charges read.

David Colbert walked to the edge of the garage and saw a man later identified as Shillingford hiding around the corner. John Colbert then came outside with a gun, and Shillingford shot him.

With John Colbert on the ground and bleeding, David Colbert picked up the victim's gun and shot at Shillingford but missed.

Law enforcement officers arrived and located 9-millimeter shell casings from where Shillingford had been when he opened fire.

One of the officers spotted Shillingford running toward the driveway of a nearby home, and he was arrested about 30 minutes after the shooting without resisting.

"Shillingford was extremely belligerent and continued to yell out random names," the charges read.

A sheriff's deputy searched an events center nearby and located a 9-millimeter handgun and magazine near a broken window.

John Colbert was wounded in the right arm, striking an artery, and the right side of his torso. Emergency responders declared him dead within 30 minutes of the shooting from what appeared to be the same gunshot.

At the news conference, Olmstead County Attorney Mark Ostrem said John Colbert acted legally by arming himself, and the son was also within his rights to shoot at Shillingford.

"There was nothing wrong about the victim having a firearm and responding the way he did," Ostrem said, and "there would be nothing unlawful about" the son's actions, either.