MMA Fighter Turned Anti-Gun Activist Convicted in Son’s Death Revenge Case; Police Call It 'Tit-for-Tat'

A Mixed Martial Arts Fighter, who became a high-profile anti-violent and gun activist, was convicted of murder. The activist killed another man right after one of his anti-gun violence rallies. The man whom he killed was allegedly connected to his son’s death.

A 47-year-old Mixed Martial Arts Fighter, Lumumba Sayer Sr., was convicted of second-degree murder on April 27. Sayer Sr. was charged for fatally shooting another man, identified as Malcom Watson, at a birthday party.

Watson was attending his 5-year-old son’s birthday at a park in Commerce City, just outside of Denver, in August 2024, when he was fatally shot.

Prosecutors argued that Sayer Sr. killed Watson because he believed he was involved in a mass shooting in 2023 that killed Sayer Sr.'s son, Lumumba Sayer Jr., according to the Denver Post.

Sayer Sr., the celebrity Mixed Martial Arts fighter, lost his son in a mass shooting in 2023, and ran an anti-violence foundation in his name called “Gloves Up, Guns Down: Get Your Heads Up in the Woods.”

He held an anti-gun violence rally on the day of the incident and then drove directly to Watson’s son’s party, where he fatally shot him at close range.

Other witnesses present at the 5-year-old’s birthday party were also present at the 2023 mass shooting incident, where Sayer Sr.’s son died. The witnesses included Sayer Sr.’s daughter and the mother of Watson’s children. Both were injured during the mass shooting in 2023 that killed Sayer Jr. Authorities described the attack as a tit-for-tat attack.

Authorities arrested an individual in connection with the mass shooting identified as Tyrell Braxton.

Braxton, 24, was convicted and sentenced in 2025 to 16 years in prison.

Witnesses said that Watson was a friend of Braxton, the man convicted in the 2023 mass shooting, and Sayer Sr. wanted revenge. The desire for revenge led to Watson's killing.

After the incident, authorities arrested Sayer Sr. and charged him with first-degree murder, which would have automatically led to a sentence of life in prison. However, the jury acquitted him of that charge and instead found him guilty of second-degree murder and other felony charges. The other charges included tampering with evidence and attempted tampering with evidence.

Sayer Sr. is scheduled to be sentenced on July 24, 2026.