MADISON, S.D. >> From the moment 73-year-old Carl Ericsson rang his old high school classmate’s doorbell in January, verified the man’s identity and then shot him dead, the question had been what prompted him to confront a man he hadn’t even spoken to in years.

The startling answer, a prosecutor said Friday, was a 1950s locker room humiliation that festered in Ericsson’s mind for a half-century.

“He said that a jockstrap was put on his head,” Kenneth Meyer said. “It’s the only thing he’s ever mentioned in talking to law enforcement.”

Ericsson, who a psychiatrist said suffered from anxiety and depression for years, last month pleaded guilty but mentally ill to second-degree murder in the death of Norman Johnson.

“I guess it was from something that happened over 50 years ago,” Ericsson told a judge then. “It was apparently in my subconscious.”

He was sentenced Friday to life in prison.

Johnson was a track star at Madison High School, and Ericsson a student sports manager. The prosecutor said he had no other details about the locker room story, which never was corroborated.

“I know of no one that remembers it or acknowledges it other than Carl,” Meyer said.

He also declined to say whether in Ericsson’s telling, it was Johnson who put the jockstrap on his head.

Beth Ribstein, Johnson’s youngest daughter, said she couldn’t understand how someone could hold onto a grudge for so long.

“It was just goofing off in a locker room,” Ribstein said, shaking her head.

Ribstein, 50, addressed the court before Ericsson was sentenced, and accused him of envying Johnson’s success in the Madison community.

After high school, Johnson played college football, earned a bachelor’s and a master’s degree and returned to Madison High to teach and coach for more than 30 years.

More than 600 people — about one-sixth of Madison’s population — attended Johnson’s funeral, including one of Ericsson’s family members. Johnson was well-liked and respected across the community, Ribstein said.

“I can’t blame you for being jealous of dad,” she said to Ericsson.

Ericsson himself was no failure.

He had lived in Wyoming before returning to South Dakota and settling in Watertown, a town nearly an hour north of Madison. He has been married to his wife, Deanna, for more than 44 years, is a North Dakota State University graduate and recently retired from a 25-year insurance career, his attorney, Scott Bratland, has said.

But Ericsson was not well. In an affidavit supporting Ericsson’s change of plea, psychiatrist Robert Giebink wrote that Ericsson has a long history of anxiety problems and suffers from “severe and recurrent depression that is, for the most part, treatment resistant.” Giebink said Ericsson was significantly depressed and suicidal when they first met in January.

“Thinking was irrational. Judgment was impaired,” Giebink wrote. “He made the comment that he wished each night that he would not wake up in the morning.”

Investigators first learned of a potential past incident between the two from Ericsson’s brother, Madison attorney Dick Ericsson. Ericsson said in the arrest affidavit that “there was an incident where Norm Johnson did something to Carl.”

Dick Ericsson has refused interview requests and declined comment again Friday. No published phone listing could be found Friday for Ericsson’s wife.

In brief comments to the judge Friday, Carl Ericsson did not address the grudge but said he would like to tell Johnson’s widow, Barb, that he was very sorry for what he had done.

“I just wish I could turn the calendar back,” he said.

Ericsson pleaded not guilty to a first-degree murder charge in February and requested a jury trial. But Meyer and Bratland announced May 1 that a deal had been reached. The first-degree murder charge could have carried the death penalty if prosecutors chose to pursue it.

A defendant can be sentenced to the state penitentiary under South Dakota’s “guilty but mentally ill” law. Treatment for the mental illness can be given in prison, or the inmate can be transferred to other facilities under the jurisdiction of the Department of Social Services for treatment and then returned to the penitentiary to complete his or her sentence.  

Johnson’s oldest daughter, 52-year-old Terri Wiblemo, noted in court that Sunday is Father’s Day, and each year her dad looked forward to enjoying his favorite meal of fried chicken, potato salad and rhubarb pie.

“We miss my dad very much,” she said.