Daniel Pantaleo, the NYPD cop who placed Eric Garner in a chokehold before he died, will finally face a disciplinary trial years after the fact, NBC reports.

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A federal grand jury has been investigating Pantaleo since the death of Garner on July 17, 2014, after Garner was selling loose cigarettes on New York’s Staten Island. Pantaleo constricted Garner, and his final words, “I can’t breathe,” became a rallying cry for protest movements across the country. Even though Garner’s death was ruled a homicide, Pantaleo was not convicted by a Staten Island grand jury.

Pantaleo will go to trial May 13, and the trial could take about two weeks, the judge said. Pantaleo’s legal team tried and failed to get the judge to postpone the trial.

If justice prevails, Pantaleo could be fired from the department or lose vacation days,  seemingly paltry in light of Garner’s death.

Pantaleo has been on desk duty and had his gun privileges revoked.

Garner’s mother Gwen Carr attended the hearing—a moment in time that was surreal for the still grieving woman.

“I felt sort of numb being in the same room as my son’s murderer,” said Carr.

Carr wants Pantaleo’s fired.

The police union, the Patrolmen’s Benevolent Association, defended Pantaleo saying he had used “the least amount of force necessary” and said his windpipe was not crushed during the chokehold.

“This case demonstrates the danger that is inherent in prejudging incidents absent all of the information that must be considered in order to come to a truthful and accurate conclusion,” Union president Patrick Lynch said in a statement.

The haunting and brutal video of Garner dying at the hands of New York police officers is traumatic for many who have seen it, but the circumstances surrounding his horrific death are becoming faint memories that are hard for witnesses to recall.

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According to a new court filing by the Civilian Complaint Review Board, the investigation into Garner’s 2014 death has languished on so long that the time lapse has caused the medical examiner and witnesses to forget key facts in their grand jury testimony, the NY Daily News reports.

Recently, the agency argued that their grand jury testimony needs to be unsealed to help them recall facts as the agency works to prosecute Officer Pantaleo at his upcoming NYPD disciplinary trial.

“The M.E. stated that she wanted to make sure that her testimony at the … trial was consistent with her testimony that she had given to the grand jury and to the (Department of Justice.) However, that would be difficult because of the amount of time that elapsed since those testimonies,” wrote Kerry Jamison, the CCRB’s assistant general counsel.

The NYPD issued disciplinary charges against Pantaleo in July. They first said they would wait until the Department of Justice finished its civil rights investigation into of Garner’s death, but it was taking too long and it has been four years so they moved ahead with disciplinary charges against him.