A man accused of trying to kill a state trooper following a traffic stop was convicted Thursday on all his charges, a few hours after his travel companions were sentenced to prison.

A Pennington County jury found 35-year-old Donald Willingham guilty of attempted first-degree murder, aggravated assault on a law enforcement officer, possession of marijuana with intent to distribute, possession of marijuana, as well as commission of a felony with a firearm.

The verdict came about five hours after the jury was handed the case just before noon Thursday — and two years after Trooper Zachary Bader stopped a Chevrolet Suburban along Interstate 90 near Box Elder. The SUV, carrying Willingham and three others from Seattle, was pulled over for speeding and was searched after Bader smelled marijuana inside.

Bader found marijuana in the vehicle’s back cargo area and was about to handcuff Willingham when Willingham punched him to the ground and continued swinging, jurors were told in the course of the four-day trial.

“If you want him down, he is down. If you want to get away, you can get away. It is only if you want him to die that you need to continue the beating at this point,” county state’s attorney Mark Vargo said in his closing argument Thursday morning.

Willingham, in a recorded police interview played for the jury, admitted assaulting Bader. The Renton, Wash., man said he didn’t intend to hurt the trooper but was afraid of going to jail for transporting 40 pounds of marijuana and of Bader confiscating his $30,000 in cash.

“Nothing was premeditated,” lead defense attorney Dennis Doherty said in his closing argument, referring to Willingham’s attempted murder charge. “This was a spontaneous act of fury, a lack of impulse control.”

Doherty said his client gave a false confession, taking all the blame because he wanted to protect his girlfriend, who was present, and the child she was carrying.

A woman who witnessed the attack, and the first person to call 911, testified Thursday she saw two men kicking the trooper after he was knocked down to the ground by a different man. Doherty said this showed Willingham’s two male companions were as culpable in the trooper assault; Vargo said the witness statement was inaccurate.

Doherty denied also that Willingham was guilty of the firearm charge, saying the handgun that police found with the drugs belonged to one of his male travel companions.

That man, 24-year-old Jonathan Melendez, was sentenced Thursday afternoon to 1-1/2 years in prison for possession of marijuana with intent to distribute and being an accessory to a crime.

He and Willingham’s then-girlfriend, Desiree Sukert, as well as her brother, Chase Sukert, pleaded guilty last year to the same two charges. Melendez received the most lenient punishment after authorities found him to have been the most honest and cooperative, and law-abiding since he was released on bond.

On Tuesday, Melendez testified against Willingham in accordance with his plea deal with prosecutors.

The Sukert siblings, meanwhile, were not called to testify despite their plea agreements. Vargo told the judge that Desiree Sukert, 28, maintained contact with Willingham up to “just days ago,” leaving the prosecution doubtful she was truly on their side and understood the gravity of her offenses.

She was sentenced to five years in prison.

Chase Sukert, 25, was given 11 years. The court was told he has a pending charge in Washington state after being involved in a car chase with police last year. He apparently crashed and would have been killed if he hadn't been rescued by a state trooper.

Retired 7th Circuit Judge Wally Eklund, who continued to preside over the case, reprimanded the three defendants for not coming to Bader’s aid and for driving away with Willingham. All four were arrested in Wall, about an hour after they left Bader bleeding badly beside the interstate.

Melendez and the Sukerts, all Washington state residents, individually apologized to Bader, who attended the sentencing hearings and the verdict announcement.

Bader sat beside his wife in the first row of the gallery as the judge read Willingham’s five guilty verdicts.

Contact Tiffany Tan at tiffany.tan@rapidcityjournal.com.

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