Shane Tweedy will spend at least 37 years in the state penitentiary for killing Yankton resident Patrick Montgomery last May.

Circuit Judge Glen Eng sentenced the 29-year-old Crofton, Neb., man Thursday to 150 years in the state penitentiary with 100 years suspended provided that Tweedy follows various terms upon his release. Because of a history of violent crimes, Eng said Tweedy will have to serve out 75 percent of his 50-year sentence before being eligible for parole.

Tweedy had been charged with first-degree murder in connection with the May 22, 2008, shooting death of Montgomery. As part of a plea agreement reached in February, the charge was reduced to homicide as manslaughter in the first degree, which requires that the perpetrator had no design to cause death.

Approximately 20 people sat in the Yankton County Courthouse and Safety Center for Thursday morning’s sentencing, during which Tweedy offered an apology to the victim’s family.

“I would like to say I’m sorry for my actions,” he said. “I regret what I did to the Montgomery family.”

At the center of discussion on both sides of the bench was the role mental illness did and did not play in the crime.

Tweedy has been diagnosed with paranoid schizophrenia. Legal proceedings have been held up for months as he has undergone two psychiatric evaluations, the first of which found him incompetent to stand trial. The second one was completed earlier this year and deemed him ready to move forward.

No one was called to testify during the sentencing. Deputy Yankton County State’s Attorney Erich Johnke said the only people he would have called upon were Montgomery’s two children, who declined to speak during the proceedings.

“Patrick Montgomery was a father … grandfather … and friend of many,” Johnke began, before requesting that Tweedy receive a life sentence for his role in killing the Yankton man.

Tweedy was aware that his mental condition was deteriorating but was unable to recognize that he needed help, Johnke added. A life sentence is the only way to protect the public from such an individual, he said.

Most individuals suffering from mental illness receive help and do not commit homicide, Johnke continued.

“Mr. Tweedy is an exception,” he said.

Judging from his actions before and after the crime, Johnke said Tweedy knew what he was doing.

“Mr. Tweedy knew what he did was wrong,” he said.

Defense attorney Dan Fox referred to a doctor’s report that stated Tweedy was so “psychotically deranged” at the time of the crime that he could not contain his actions within the confines of the law.

“It does not excuse what happened,” Fox said. “But it does explain what happened.”

When Tweedy was arrested for the murder of Montgomery within hours of the crime, Fox said he had never seen a person in such poor mental condition.

Tweedy was hearing voices that were threatening harm to him and his family, Fox explained. He believed Montgomery, who was the father of Tweedy’s ex-girlfriend, had something to do with the threats and intended to warn him to stop them that May morning. Even after law enforcement told Tweedy what he had done, Fox said he wasn’t convinced of what had taken place. Tweedy believed Montgomery wasn’t actually dead and that it was part of a conspiracy against him.

Fox first encountered Tweedy when he was charged with driving under the influence. Fox said he recognized something was wrong with Tweedy at that time and while Tweedy was serving time in jail for that crime, his mental health deteriorated. He was taken to the South Dakota Human Services Center and given medication for schizophrenia.

However, Fox said that, after Tweedy was released, another doctor determined he did not have schizophrenia and took him off medication. That led to an approximately 10-month stretch of declining mental stability during which Tweedy began hearing voices.

Since being incarcerated for Montgomery’s death and receiving treatment, Fox said he has seen a “night and day” difference in Tweedy, who can now interact with the general population in the jail and no longer displays the symptoms of mental illness he did initially.

“What a terrible tragedy this is for all involved,” Fox said.

Tweedy didn’t commit the crime because he is an evil or violent person, the defense attorney continued. Instead, it was the result of “a terrible chain of circumstances” during which Tweedy sunk deeper into paranoia.

“It’s very difficult to grasp,” Fox said of Tweedy’s mental state.

He asked that Tweedy be given an extended suspended sentence during which he would be required to receive mental health treatment.

Eng noted that a pre-sentence investigation resulted in a 399-page document, and began by recounting Tweedy’s crime.

On the morning of May 22, Tweedy traveled from his home to his parents’ residence and retrieved a shotgun from a gun case to which they were not aware he had access. He drove to Yankton and parked his vehicle a significant distance from Montgomery’s house in the 2000 block of Elm Street. After ringing the back doorbell of the house, Tweedy retreated behind a shed. When Montgomery answered, Tweedy fired at least four shots and left the scene. He drove back to his parents’ house, placed the weapon back in the case and went home, where he was later apprehended by law enforcement.

Eng went on to recount several previous cases in which Tweedy was charged with assault, including one instance where he put a gun to a person’s head. He also pointed to an interview during which Tweedy admitted to driving around Yankton with a gun, contemplating whether he would shoot someone randomly.

All those events occurred before Tweedy reported he began hearing voices, Eng said.

The judge went on to say that if he believed Tweedy’s shooting of Montgomery was strictly due to mental illness, his sentence would be different. However, the history of violent incidents indicates there is something more at work, Eng said.

“There is a violent behavior that is embedded within you,” he said. “I’m not saying that can’t be changed. I’m not saying that can’t be overcome.”

With that, Eng rendered his sentence of 150 years with 100 suspended, adding that Tweedy will receive credit for the time he has served already.

(1) comment


I am happy the guy is off the streets! However he should of been placed in a mental institution years ago. I don't think it's proper to incarcerate mentally ill people along side hardened criminals.

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