A Hennepin County jury reached speedy verdicts Tuesday evening, convicting a taekwondo master from St. Paul of aiding first-degree attempted murder in connection to the ambush shooting of a Minneapolis police crime scene investigator, the mother of their son.

After two weeks of testimony, it took jurors roughly an hour of deliberation to find Timothy Amacher guilty of aiding first-degree attempted murder and aiding an accomplice after the fact. He is accused of plotting to kill Nicole Lenway with the help of an ex-girlfriend and former student, Colleen Purificacion Larson, in order to gain full custody of his 6-year-old son.

Lenway was among dozens of witnesses called to the stand throughout the trial. She was shot on April 20 at point-blank range in the neck and testified for eight hours about her toxic relationship with Amacher, whom she met at his martial arts studio in 2012.

Assistant Hennepin County Attorney Patrick Lofton said in his closing argument Tuesday that Amacher is the only person with the motive to kill Lenway, who miraculously survived the shooting and "10 years of hell that he's put her through."

"All that harassment, all that stalking, abuse, threats, false reports of child abuse," Lofton said. "Throughout that you start to get a sense of who this man is, of his worldview, of how far he's willing to go."

Larson, 25, has said Amacher, 41, pressured her into carrying out the attack outside FamilyWise, a supervised visit and exchange center in Minneapolis where Amacher had weekly visitation with his son.

Larson is charged with attempted first-degree murder. Her trial is set for January.

While Amacher was inside FamilyWise with his son, surveillance video showed Lenway walking up to the facility and Larson running up from behind with her arm extended. Lenway fell to the sidewalk after the first shot, and she testified that Larson stood above her and fired again.

"What would drive [Larson] to try to do this?" Lofton said. "It's not her son she doesn't have custody of. It's not her son she has to see under lock and key. She's not the one who has been in a four-year custody battle."

"This was an assassination attempt, it's just that simple," Lofton said.

Prosecutors pointed to key pieces of evidence that they say showed Amacher's premeditation and coordination with Larson: The day before the shooting, he registered for a new license plate on his Dodge Ram truck that Larson used to drive that day to FamilyWise, and she arrived seven minutes before Lenway. On the day of the shooting, the truck is without plates; the day after, temporary plates were on the truck.

Amacher didn't tell police immediately after the shooting that he owned a Dodge Ram, Lofton said. He also didn't express any concern when police told him that the mother of his son was shot just outside the building.

"It had nothing to do with me," he told police inside FamilyWise, recorded on officer body-worn cameras. "I didn't even hear gunshots."

The weapon, a .380 handgun, was never located. Amacher said he had owned two. One he sold to Steve Schleicher, a trial attorney who served on the prosecution team in the Derek Chauvin trial and who testified that he bought the firearm from Amacher.

Amacher told police he gave the other .380 to Lenway, which she denied in testimony. An empty .380 case was found in Amacher's home, along with spent shell casings. A firearm expert testified that they matched the casings at the crime scene.

Lofton said the biggest smoking gun is the fact that no phone calls or text messages were exchanged between Amacher and Larson during and after the shooting, which suggests they had the attack planned.

Amacher's attorney, Larry Reed, asked Judge Shereen Askalani to acquit his client of the charges because he said the state did not present any evidence that proved Amacher aided and abetted Larson. Askalani declined. Reed didn't call any witnesses to the stand and Amacher waived his right to testify.

Reed said in his closing argument there is no evidence or testimony that Amacher gave Lenway a .380 gun. He said Amacher "100 percent cooperated" with police, handing his phone over to police and sharing with them his concern about Lenway allegedly abusing their son.

"All he wanted was for her to be a good mother to her son," Reed said.

He told jurors that he would have understood if they found the weeks of testimony a "needless waste of time" as it focused too much on Larson, child custody and smearing of Amacher.

"But you are his only hope," Reed said. "He cannot get justice without you."

Amacher will be sentenced Jan. 18.