Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

A white former South Carolina police officer pleaded guilty Tuesday to violating the civil rights of Walter Scott, the unarmed black motorist he shot dead in 2015.

The state of South Carolina, as part of a plea deal, will not file new charges against Michael Slager, who was fired after cellphone footage of Scott's killing in North Charleston went viral. Slager's murder trial ended last December in a hung jury.

"The defendant used deadly force even though it was objectively unreasonable under the circumstances," the plea agreement says.

Related: Judge Declares Mistrial in Murder Trial of Former Cop Michael Slager

Outside the courthouse Tuesday, Scott’s brother, Anthony, thanked federal prosecutors and said his family was grateful to have “justice.”

The Morning Rundown Get a head start on the morning's top stories. This site is protected by recaptcha

“For me and my family, the healing starts today,” Anthony Scott said, adding that Slager’s guilty plea was a “victory” for his city, state, country and the world.

Walter Scott’s mother, Judy, fought back tears as she told reporters she forgives Slager.

"I forgive Michael Slager because the forgiver is in me. That he [Slager] admitted he did it was enough years for me," she said.

Slager, 35, pulled over Scott on April 4, 2015, due to a broken taillight. Scott, 50, then ran from the traffic stop. The incident escalated, Slager has claimed, when Scott wrestled away the officer's Taser. Slager then fired his weapon as Scott ran away. Scott was struck five times in the back.

The defense in Slager's murder trial claimed the former North Charleston police department patrolman feared for his life and fired in self-defense. Scott's family has suggested he fled because he owed back child-support payments and did not want to be arrested.

Slager's federal trial was set to begin on May 15, and jury selection was slated to begin May 9.

The former officer pleaded guilty to violating Scott's civil rights by shooting him with no justification — formally known as deprivation of rights under color of law. The charge carries a maximum penalty of life in prison.

"We hope that Michael's acceptance of responsibility will help the Scott family as they continue to grieve their loss," Slager's lawyer, Andy Savage, said in a statement. Sentencing has not yet been scheduled, Savage said.

Slager was also indicted last year on charges of using a firearm in committing a crime of violence and obstructing justice. Those two charges will be dismissed under the terms of the plea deal.

After the mistrial in December, state prosecutors said they would seek to try Slager again, but no charges had yet been filed.

The infamous cellphone video was viewed millions of times worldwide. It was recorded by bystander Feidin Santana, who revealed himself first to "NBC Nightly News" anchor Lester Holt.

The shooting itself heightened tension nationwide over alleged excessive use of force by law enforcement and systemic racism in policing.