A 3D-printed gun and a man in a tan tracksuit were details that led the defense’s opening arguments in Lumumba Sayers Sr.’s murder trial.

Sayers Sr., a former MMA fighter and Aurora anti-violence activist, appeared in the Adams County District Courtroom Tuesday morning in a gray suit. He looked frail, significantly smaller than the weight he appeared in security camera footage on Aug. 12, 2024, when he was arrested on charges in the death of 28-year-old Malcolm Watson.

He faces charges of first-degree murder, two counts of felony menacing and two counts of tampering with evidence after allegedly shooting and killing Watson nearly a year after his son, Lumumba Sayers Jr., was killed in a shooting.

The defense and prosecution seated the jury Tuesday morning, leading to opening statements and witness testimonies from officers of the Commerce City Police Department.

The prosecution, led by 17^th Judicial Deputy District Attorney Laura Anderson, opened the trial with security footage of Sayers Sr. walking up to Watson outside of the Paradise Island Pool in Commerce City around 5 p.m. that day.

Around 30 people were outside of the pool for Watson’s son’s fifth birthday party.

Sayers Sr. allegedly walked up to Watson and shot him in the head, killing him, though four spent casings were found around the parking lot.

The video showed the man then bent down next to Watson and allegedly rummaged through his pockets, with Audell Thomas, the mother of Watson’s son, attempting to film Sayers Sr. and saying, “You’re going to jail. You’re going to jail… Stop putting sh** in his pockets.”

Sayers Sr. was then seen going back to the black Cadillac SUV he arrived in and firing off another shot, according to witnesses. He came back, ejected the clip and placed the gun on the ground near Watson – a detail debated by the defense.

The prosecution claimed that the act was based on revenge over the death of his son.

Sayers Jr. was shot and killed on Aug. 19, 2023 at 28th and Welton streets in Denver. The quadruple-victim shooting left Sayers Jr. and 25-year-old Gulian Musiwa dead.

Sayers Jr. was allegedly protecting his sister during the shooting.

The sister allegedly attended Watson’s party with Sayers Sr. Arrest records claim Watson and Sayers Jr.’s alleged shooter, Tyrell Braxton, were friends.

Anderson told jurors that Watson was part of the east side of Denver, the same area as the man who shot and killed Sayers Jr. in August 2023.

“It’s just a lot of hatred and retaliation,” a witness told police in bodycam footage.

According to the prosecution, Sayers Sr. had told an acquaintance that “all east side has to die” and was “obsessed with the murder and wanted revenge.”

Sayers Sr. was wearing a memorial shirt for his son during the shooting.

The defense argued that it cannot be proven that Sayers Sr. actually shot Watson because the gun was never found.

The handgun that belonged to Sayers Sr. — the one found on the ground —had a full clip and had not been fired.

Both the defense and prosecution agreed that a ghost gun (or 3D printed handgun) was used to kill Watson, but who fired it is up for debate.

“Mr. Sayers didn’t pull the trigger of the gun that killed Malcolm Watson,” defense attorney Megan Downing said. “Something is missing.”

Downing argued that there was another shooter involved, an unidentified man in a tan tracksuit. Witnesses after the shooting mentioned a person in a tan suit firing a gun, according to the arrest affidavit.

One witness even claimed the man said, “I got you.”

Downing continued that the violence would have been the “opposite of everything he is” and that Sayers had “built his life around these foundations and helping young people avoid gangs.”

In 2015, Sayers Sr. built a community center in an unassuming building at 2360 Dayton in Aurora and called it Heavy Hands, Heavy Hearts Center. The foundation’s aim was to pull kids off the streets with movie nights, Thanksgiving dinners, fitness classes, mountain camping trips and girl’s empowerment gatherings. Fundraising events were aimed at youth violence prevention.

Downing said Sayers Sr. had just come from an anti-violence rally, hence the shirt of his son, and had a gun on him because of his work being dangerous. Though he was not invited to the party, he came because he was looking for his daughter and granddaughter.

Sayers Sr. heard a gunshot first and responded in self-defense, according to Downing. He then ejected his clip and laid the gun on the ground because “that’s what he is supposed to do.”

The defense claimed that Sayers Sr. stayed on the scene, cooperated with police and did not fire his weapon. Meanwhile, the mysterious, tan-suited man fled the scene immediately after the shooting.

The prosecution argued that the various videos speak for themselves and the witnesses who will speak of the second shooter were not a part of the party and are not reliable.

“None of those witnesses were the people who were present,” Anderson said. “They didn’t have any reason to be looking down at the pool area until they heard those gunshots.”

Everyone involved with the party, on the other hand, says that Sayers Sr. shot Watson alone, the prosecutor told jurors.

The trial will continue on Wednesday with more witness testimony and is expected to last two weeks.