The city police department's top doctor determined an officer did not put Eric Garner in a chokehold in the fatal confrontation on Staten Island in 2014, the officer's defense lawyer said Thursday.

Speaking to news reporters in lower Manhattan after a hearing for NYPD Officer Daniel Pantaleo, accused of using excessive force in the death of Garner, Stuart London said he told an NYPD administrative judge that NYPD Chief Surgeon Eli Kleinman made the conclusion.

"Dr. Kleinman, who is the Number One doctor for NYPD, had written a report, an extensive report, indicating no misconduct on the part of Officer Pantaleo," London said to the news media.

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London said the police commissioner asked the chief surgeon to review the video.

Garner died after he got into a confrontation with police when they tried to arrest him for allegedly selling loose cigarettes, which is illegal. Viral video showed Garner repeatedly saying "I can't breathe." A grand jury on Staten Island declined to charge Pantaleo.

Pantaleo is slated to face an administrative trial next month on departmental charges he used a banned chokehold on Garner, who died in the encounter.

London's comments at Thursday's hearing marked the first time Kleinman's conclusion was made public. London said it must be allowed as evidence.

"Indicating that the compromised cardiovascular system of the decedent was his main causation with respect to why he passed away," London said.

That finding would appear to conflict with the conclusions of the city's medical examiner, who said compression of the 43-year-old's neck and chest led to his death in the summer of 2014.

"Said that it was not a chokehold by looking at the video," Gwen Carr, Garner's mother, who was in the courtroom for the hearing, said at a rally for her son outside the courthouse. "You can say anything … you are an expert and you didn't look at the autopsy. What kind of expert are you?"

Pantaleo's attorney also tried to get the Civilian Complaint Review Board (CCRB) tossed off the case as prosecutors. But, the police judge said the NYPD oversight agency has the legal right to try the case.

"London trying to toss the case out and dismiss the CCRB was a disgrace," Carr said. "That was an insult."

The NYPD disciplinary trial is scheduled to start May 13. Carr says she plans to be present every day to hear all of the testimony. If found guilty, he could either be fired or lose vacation time and pay.

Nearly five years after the deadly confrontation, Pantaleo remains on modified duty, getting a paycheck but is barred from carrying a gun.

The Department of Justice has not announced whether it would move forward with federal civil rights violations against Pantaleo or any of the other officers involved in the confrontation.