MEMPHIS, Tenn. —  A former Memphis police officer, who pleaded guilty last month to federal charges in the 2023 death of Tyre Nichols, testified Monday that officers had "exaggerated" Nichols' behavior and that Nichols posed no threat to officers during a traffic stop that quickly escalated into a violent beating.

Emmitt Martin III was called to testify Monday in the federal trial of his three former colleagues — Tadarrius Bean, Demetrius Haley, and Justin Smith Jr. — who are accused of violating Nichols' civil rights after a traffic stop. Nichols, 29, who was Black, was pulled over on Jan. 7, 2023, and beaten by five now-former officers with the Memphis Police Department.

The three defendants in the case are charged with using excessive force, deliberate indifference, conspiracy to witness tamper, and witness tampering. The two other defendants, Martin and Desmond Mills Jr., pleaded guilty to using excessive force and conspiracy to witness tamper ahead of the trial.

As part of their plea deals, Martin and Mills are testifying against the other defendants. Martin's testimony was the first time jurors heard from one of the officers involved in the beating, in which he detailed the events that preceded Nichols being pulled over.

Graphic video footage from the traffic stop showed officers attacking Nichols using pepper spray, a Taser, and a baton while also punching and kicking him. Nichols was heard crying for his mother as officers continued to strike him.

The footage later showed the officers propping him up as he repeatedly slumps to the ground. Nichols was hospitalized in critical condition and died three days after the incident.

The five former officers were fired shortly after Nichols' death. The case drew national attention, sparking widespread protests and calls for police reform — leading to a U.S. Department of Justice probe into the city of Memphis and its police force.

When the officers are Black:Tyre Nichols' death raises tough questions about race in policing

Former Memphis officer testifies that felony stop was 'exaggerated'

During a brief testimony on Monday, Martin said the SCORPION unit officers "exaggerated what they did" in order to "justify what we did."

Martin and his former colleagues were members of the now-disbanded SCORPION unit, a specialized police unit that patrolled "hot spots" for crime in Memphis. The former officers would often overplay suspects' actions during incidents to justify their use of force, according to ABC24 Memphis and The Associated Press.

Martin, the officer who initially called in Nichols' vehicle, said he was at a stop light when he saw Nichols speed up to beat a red light. Nichols then "took off fast" and was changing lanes without a signal, according to Martin.

He said he ran Nichols' plates because beating the red light gave him probable cause. Federal prosecutor Kathryn Gilbert asked Martin what the result of the license plate search was.

"It was clean," he replied.

Martin said he followed Nichols with his police car lights on and called the SCORPION unit's private radio frequency, in which Haley told Martin to "let him take care of it."

Martin said he did not say what offenses Nichols had committed, but told Haley that Nichols was "getting small on him," meaning that Nichols was fleeing from Martin. Fleeing in a vehicle would be a felony offense, according to Tennessee state law.

Haley then pulls over Nichols and leaves his unmarked police vehicle with his gun out, which Martin said spurred him to pull his own gun out. The two officers approached Nichols' car and Haley said: "Get the f— out the car," Martin testified.

Gilbert asked why Haley and Martin surrounded Nichols' car the way they did. Martin said it was "because of the type of stop it was."

"What type of stop was it?" Gilbert asked. "A felony stop," Martin replied.

"Was it a felony stop?" Gilbert asked again. "No, it was not," Martin said, adding that he had "exaggerated" it.

After Haley told Nichols to get out of the car, Martin said Haley "snatched him out the car," not giving Nichols time to comply.

'He wasn't a threat'

Earlier in his testimony, Gilbert asked Martin what was valued on the SCORPION Unit. Martin said "stats," such as felony arrests along with confiscating guns, drugs, and money, were valued most.

Martin said he had not made any arrests that night and that he was "angry."

In the months preceding Nichols' beating, Martin said he was on desk duty because he was hit by a car. He was cleared to return to the field on Jan. 3, 2023, and said he was nervous and "seeing red."

"I was angry, I wanted some kind of revenge," Martin said.

Martin's testimony also shed more light on the "run tax" that Assistant U.S. Attorney Elizabeth Rogers mentioned during her opening statement last week. Rogers had said the beating Nichols received was known as "the run tax" by Memphis police.

"You get your a— beat," Martin said when asked what happens when someone runs from officers. He added that he knew of the consequences, but did run taxes anyway.

Martin also provided additional context to the training he received when putting someone in handcuffs. According to Martin, "If one officer had hands on him, we all need to have hands on him."

In describing Nichols that night, Martin said he was "passive" even as he pulled his hands away from other officers.

"He wasn't a threat," Martin said.

Contributing: Rick Jervis and Jessica Guynn, USA TODAY