The fighter, who is mixed with martial arts that saw Minneapolis police chief Derek Chauvin be arrested in May 2020, George Floyd told a judge on Tuesday that he had called 911 after watching the incidents because he believed he had "witnessed the murder."
The trial lasted until the second day of Tuesday for Cauvin, a 45-year-old former official who appeared in a video holding his knee on Floyd's neck for about nine minutes during his arrest on May 25. He faces charges of murder and second and third degree murder.
Donald Williams, a loser who claims to have been trained to fight MMA, including strokes, began testifying on Monday, in which he described the arrest allegedly used by Chavin "as a blood clot."
On Tuesday, he continued his explanation, recalling that Floyd's eyes "turned a little back".
"You could see he was in a lot of pain," Williams continued. "You could see he was trying to breathe, and he was trying to breathe as he was down here. He was trying to move his face in the direction of ... I think, I'm breathing."
He said he felt Floyd was "in great danger".
He remained at the scene, and when an ambulance and paramedics arrived, he said Cauvin kept his knee on Floyd's neck as they did so. He also added that when someone is alerted during an MMA fight, the simulation is stopped "immediately," and medical professionals are brought in "immediately."
Williams said he later called police because, "I believe I saw the murder."
During the phone call, Williams told the officer, "Officer 987," who identified him as Chavin, "killed the boy who was not in custody."
"He had put his knee around the man's neck all the time," Williams said during a phone call. "He was not against being arrested or anything. He was just handcuffed."
Williams could be heard on the phone saying, "Y'all don't kill them," and added: "They just killed that man in front of the store."
During cross-examination on Tuesday, Cauvin's attorney Eric Nelson asked Williams if he had ever failed a person, only to regain consciousness and start fighting again.
"Personally, no. Have I seen you? Yes," he replied.
"I've seen it many times in the UFC where, when someone strangles, they go back to them and keep trying to fight," he said. "I was released and I had to get back up and the first thing I wanted to do was keep fighting."
Nelson also wanted to show that Cauvin and his colleagues found themselves in a tense and disturbing situation, with a crowd of spectators worried about Floyd's treatment.
Nelson revealed that Williams appeared to be growing angry at police at the scene, insulting Chavin with "harsh," "bum" and other words, and then calling Cauvin annotations, the defense attorney repeated himself in court.
Williams explained Monday how he believes Floyd's condition is getting worse "when he encounters the abuse," with his voice growing louder and his breathing becoming more active.
"Since then he has been unwell," Williams said. "She did not move, she did not speak, she was no longer healthy for her with the movement of her body."
After Williams' testimony on Tuesday, prosecutors summoned 18-year-old Darnella Frazier, who recorded a recent video of her arrest because "she was wrong, she was in pain."
Frazier said he was going to a good store with his young cousin when he arrived at the police station and sent the girl to the store because he did not want to see her "scared, scared, asking for her life."