MINNEAPOLIS (WCCO) – The Hennepin County Attorney’s Office has charged a 20-year-old man with second-degree murder, in connection with the shooting death of a Good Samaritan who was trying to help him.

Devon Derrick Parker was charged Monday afternoon in the incident. And this isn’t his first run-in with the law. Parker has several past felony assault charges against him.

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He was in court Monday for one this past September. In that case, he’s accused of assaulting medical professionals and officers who were trying to get him to a hospital because he was too drunk to function.

Police paperwork shows Parker’s girlfriend called police to check on his welfare as he was so under the influence of alcohol that he jumped out of a moving vehicle and took off.

Police called paramedics because they thought Parker was drunk and in a state of “excited delirium.” He also tried to assault, spit on and bite the paramedics. Two officers were injured in the incident.

But on Friday, police say a violent past escalated to the worst level.

Parker beat on the door of 69-year-old Thomas Sonnenberg’s north Minneapolis home. Parker was yelling that someone was trying to kill him, so Sonnenberg let him in.

Hennepin County Attorney Mike Freeman believes Parker somehow managed to grab a gun that Sonnenberg was wearing.

“The gun, which we believe was used to kill Mr. Sonnenberg, was a gun that Mr. Sonnenberg normally carried,” Freeman said. “He apparently took the loaded gun off of Mr. Sonnenberg’s hip and shot him in the head, killing him.”

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The complaint says Parker was angry that he was locked inside, and took that anger out on Mrs. Sonnenberg.

The victim’s two grown daughters spoke out on Sunday after they found out what happened on Friday.

“He was not kind to my mother during that time before the police got here,” said Rachel Baufield, Sonnenberg’s daughter.

They declined to comment further on Monday.

Sonnenberg’s family is very confused as to why Parker was on the streets based on his criminal history, and they just want to know why this happened to their dad.

“He let him in and locked him in the house with my mom and him to save this man and protect his life,” Baufield said.

The victim and suspect lived about two miles apart, but it’s unclear why he chose that house.

“We know that my Dad thought he was saving somebody. He thought that this man’s life was in danger, that’s why he let him in,” Baufield said.

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Parker’s expected in court again on Tuesday, where he likely will be charged in this case.

Reg Chapman