A federal grand jury on Friday indicted former Minneapolis police officer Derek Chauvin and three other former officers on charges of violating George Floyd’s civil rights last year during the arrest that caused his death, a move that could offer another measure of accountability in a case that sparked nationwide protests over abusive policing.

Justice Department prosecutors said Chauvin, J. Alexander Kueng and Tou Thao, who took part in apprehending Floyd, a 46-year-old Black man, will stand trial on two counts apiece. Former officer Thomas Lane will face a single charge in the case.

The announcement came less than three weeks after Chauvin, who is White, was found guilty on three counts of murder and manslaughter in a state trial that focused on his use of force. Chauvin, 45, put his knee on Floyd’s neck for more than nine minutes as Floyd was prone on the pavement and complained of being unable to breathe — an incident captured on cellphone video. His sentencing is set for June 25.

On April 20 the jury found Chauvin guilty of second and third-degree murder, and second-degree manslaughter in the May 25, 2020, killing of George Floyd. (The Washington Post)

In a separate indictment announced Friday, Chauvin also will face two federal counts of violating the rights of a 14-year-old boy during an arrest in September 2017, in which the officer is accused of holding the boy by the neck and hitting him twice with a flashlight, causing injuries.

Kueng, 27, Lane, 38, and Thao, 35, are facing state charges of aiding and abetting second-degree murder and manslaughter in the Floyd case. Their trial is set to begin in late August. Kueng is Black, Lane is White and Thao is Asian American.

The federal charges could add additional time in prison or other penalties, independent of state-level convictions.

Attorneys representing Chauvin and Kueng declined to comment for this report, while representatives for Thao and Lane did not respond to requests for comment.

“The federal government has a responsibility to protect the civil rights of every American and to pursue justice to the fullest extent of federal law,” Minneapolis Attorney General Keith Ellison (D) said in a statement. “Federal prosecution for the violation of George Floyd’s civil rights is entirely appropriate.”

Justice Department officials said the decision to bring charges against the officers was the result of a review of evidence from Civil Rights Division lawyers who have been on the ground in Minneapolis for months. Last month, Attorney General Merrick Garland announced that the department will conduct a sweeping “pattern or practice” investigation to determine whether the Minneapolis police have systemically engaged in unlawful conduct.

The intensifying federal scrutiny reflects the Biden administration’s sense of urgency in addressing abusive policing in the wake of the mass social justice demonstrations that swept the country after Floyd’s death on May 25, 2020, and the calls from civil rights leaders for sweeping reforms of law enforcement agencies. The Justice Department also recently announced a probe into the Louisville police, which has faced scrutiny since last year’s shooting death of Breonna Taylor, a 26-year-old Black woman.

Experts said that charges under federal statute 242 — which prohibits government officials, including police, from violating a person’s federally protected rights — in officer-involved deaths are rare, and convictions are more difficult for prosecutors to win than in normal self-defense cases.

The Justice Department must prove that Chauvin and the three others deliberately engaged in acts they knew were violations of Floyd’s civil rights, said Jonathan M. Smith, executive director of the Washington Lawyers’ Committee for Civil Rights and Urban Affairs.

“There’s a very small handful of cases in which the charges are brought. This is a pretty extraordinary and important indictment in that regard,” said Smith, who served in the Justice Department’s Civil Rights Division from 2010 to 2015.

He also pointed to the indictment’s timing, coming before Chauvin’s sentencing in the state case and ahead of the state trial for the other three former officers. In the past, Smith said, the Justice Department generally has waited to determine if the final verdict and sentencing in state cases against officers were sufficient in meting out justice before deciding whether it was necessary to move forward with federal charges.

“That’s a real signal about the willingness of the United States and this administration to take a different approach to officer use-of-force cases,” Smith said. “This could well be a bellwether for future cases.”

During a news briefing Friday, White House press secretary Jen Psaki said she had no “specific reaction” to the charges but noted that “there’s still more that needs to be done.” The case, she said, served as a “reminder of the need to put police reform in place through our legislative process and put those reforms in place across the country.”

President Biden backs congressional legislation named for Floyd that would impose new restraints of the use of force by officers. After Chauvin was convicted last month, the president invoked the verdict in saying that it offered “a chance to change the trajectory in this country.”

In the 10-year period from 2005 to 2014, when perhaps 10,000 Americans were killed by police, 153 officers were charged, or about 1.5 percent, according to a database maintained by Philip Matthew Stinson at Bowling Green University and cited in a Washington Post report last year.

There are known dispositions in 139 of those 153 cases, Stinson said. About 55 percent of the cases resulted in convictions, most by guilty plea. Stinson’s database also captures non-shooting cases. His research found 58 murder or manslaughter cases that did not involve a gun. Of the 51 cases with known results, about 65 percent resulted in a conviction, but only 47 percent of the cases ended with felony convictions.

Stinson said in an interview that charges against the former officers in the Floyd case are “absolutely appropriate.” The federal case, he noted, could mean that Chauvin would serve time in federal prison even if he successfully appeals his state conviction.

Floyd was sitting in a car when Kueng and Lane responded to a call from an employee of a convenience store who reported that Floyd was thought to have used a counterfeit $20 bill. Lane drew his firearm as the officers ordered Floyd out of his car and handcuffed him, with Floyd pleading with the officers not to shoot him, according to body camera footage.

Chauvin and Thao arrived at the scene, and Chauvin joined the other two as they attempted to force Floyd into the back seat of a police vehicle. In the struggle, the officers subdued Floyd on the ground, with Chauvin kneeling on his neck and Kueng and Lane holding his back and legs. Thao ordered bystanders to stay away and prevented a Minneapolis firefighter from providing medical aid to Floyd, according to cellphone video footage.

The federal indictment charges Chauvin for using “unreasonable force” in subduing Floyd and charges Thao and Kueng with failing to intervene to stop him. All four officers are charged with failing to help provide medical care to Floyd and “thereby acting with deliberate indifference to a substantial risk of harm.”

Jim Pasco, executive director of the National Fraternal Order of Police, said his organization does not represent the Minneapolis Police Department. Though he declined to discuss the specifics of the indictment, Pasco said: “The charge is a very serious one. We’re going to assume that it was made after a very, very careful investigation and thoughtful discussion at the Justice Department. That said, I will acknowledge that the [legal] bar is high and that these officers are entitled to due process just as any other American citizen would be.”

In a statement, the Rev. Al Sharpton, head of the National Action Network, hailed the indictments as a “significant development” for police reform advocates. Sharpton cited the 2014 police killings of Eric Garner in Staten Island and Michael Brown in Ferguson, Mo., in which officers did not face federal charges.

“We have a Justice Department that deals with police criminality and does not excuse it nor allow police to act as though what they do is acceptable behavior in the line of duty,” Sharpton said.

In the separate 2017 incident, Chauvin and another officer reported that they used force to subdue a teenager who resisted their commands after they arrived at a home in response to reports of domestic assault. But during Chauvin’s trial, state prosecutors cited body camera footage from the officers that showed him striking the boy with his police flashlight within 41 seconds of instructing him to exit a bedroom.

Two seconds later, Chauvin allegedly grabbed the boy by the throat and hit him again with the flashlight, before applying a neck restraint that caused him to momentarily lose consciousness, according to documents filed by state prosecutors.

A minute later, the boy told Chauvin that he could not breathe. The boy’s mother pleaded with Chauvin four times to remove his knee from his neck, prosecutors said, adding that she “also said that Chauvin had hit her son with a flashlight and hurt him, and he was handcuffed now and could not do anything. But Chauvin maintained his position.”

Holly Bailey in Minneapolis and Mark Berman and Matt Zapotosky in Washington contributed to this report.