But after 12 hours at the scene where the his truck was dumped, Jack Knysz said the more he learned, the more suspicious he became.
Butterfield, 43, was shot in the head during a traffic stop Monday and died during emergency surgery. Information he gave to dispatch before the shooting led police to track down Eric Knysz, 19, and his pregnant wife, Sarah, 21.
Jack Knysz said his son asked to borrow his truck for a doctor's visit, and Eric Knysz stopped to look at a car for sale along the way.
"Supposedly, he went to buy a car and they reported it stolen," Jack Knysz recalled. The stolen car was supposedly the one Eric and Sarah Knysz were in when police caught up with them after the shooting.
Eric Knysz exchanged fire with police at a Manistee County gas station, and was shot. He and Sarah Knysz were both taken into custody.
"None of it makes sense, I mean, the troopers have all these facts so you have to go by the facts,” Jack Knysz said.
Like Butterfield, Jack Knysz was a military veteran and a retired police officer. Along with Butterfield's fellow officers, Knysz mourns the trooper's loss.
"Being a police officer, I know how [the police] feel and it's just the worst day or your life," he said. "Our family and our hearts and our prayers to out to him and his family."
Mason County Sheriff Kim Cole, who responded when a passing motorist called 911 after seeing Butterfield on the ground, said it was a shock to see his friend struck down.
"When I arrived I saw Paul, I stayed with him, I sat with him in the ambulance and tried to encourage him," Cole said. "I know he would have done that for me and he'd done it for any of our guys."
Cole said Butterfield was "more than a coworker, he was a friend," and called Monday a "dark day for our community."
"Our deputies and law enforcement officers around the state will pull car stops, they'll be afraid, they'll think of Paul and they will carry on and they will do their job remembering Paul," he said.
Michigan Gov. Rick Snyder ordered flags be flown at half staff around the state in mourning.
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