(CNN)A
professional mixed martial arts fighter who stumbled onto the scene of George Floyd's death testified Tuesday that he called 911 after watching former officer Derek Chauvin's actions on May 25, 2020. "I called the police on the police," Donald Wynn Williams II testified Tuesday. "I believed I witnessed a murder."
Williams, whose testimony began Monday afternoon and continued Tuesday morning, is the third witness in Chauvin's criminal trial. He was one of the most vocal bystanders in the widely seen video of Floyd's final moments, repeatedly calling for officers to get off Floyd's neck.
Relying on his own MMA experience, he said that Chauvin performed a "blood choke" on Floyd and adjusted his positioning several times to maintain pressure on Floyd's neck.
Williams had gone fishing with his son earlier in the day, and he decided to go to the Cup Foods store in Minneapolis to "get some air" after watching several caught fish suffocate and die. When he came upon Floyd's arrest nearby, he watched Floyd gasp for air and saw his eyes roll to the back of his head -- "like a fish in a bag," he explained.
He said he wanted to get Chauvin off Floyd but didn't physically intervene because former Minneapolis Police officer Tou Thao was directing him to stay away. After watching Floyd leave in an ambulance, Williams called 911 to report what he had seen.
Williams is the second witness to say they reported the police's behavior to the police. On Monday, a Minneapolis 911 dispatcher testified that she was able to watch live video of Floyd's arrest at the time and called a police sergeant afterward to voice her concerns about the arrest.
"My instincts were telling me that something's wrong. Something was not right. I don't know what, but something wasn't right," Jena Scurry said she thought as she watched the video. "It was an extended period of time."
The testimony in Chauvin's trial comes 10 months after Floyd's death launched a summer of protest, unrest and a societal reckoning with America's past and present of anti-Black racism and aggressive policing.
Chauvin, 45, has pleaded not guilty to second-degree unintentional murder, third-degree murder and second-degree manslaughter charges.
In opening statements Monday, prosecuting attorney Jerry Blackwell said Chauvin used excessive and unreasonable force when he knelt on Floyd for 9 minutes and 29 seconds -- a number different than the infamous 8:46 timing that has become a symbol of police brutality. Chauvin's defense accepted the new timing as accurate.
Blackwell played the harrowing video and audio of Floyd's death recorded by a bystander to bolster his argument and offered jurors a clear and simple case against Chauvin.
"You can believe your eyes that it's a homicide," he said. "You can believe your eyes."
In response, defense attorney Eric Nelson argued that the case was more complicated than just that video. He said Chauvin was following his police use of force training and argued Floyd's cause of death was a combination of drug use and preexisting health issues.
"The use of force is not attractive, but it is a necessary component of policing," he said.
