The head of the Patrolman's Benevolent Association Tuesday criticized the mayor and blasted the Rev. Al Sharpton, the most vocal critic of the NYPD since the Eric Garner chokehold incident.

PBA President Patrick Lynch, speaking at a news conference at the union's headquarters yesterday, said the union provide experts in the use of force to prove that a chokehold was not the cause of Garner's death while in police custody last month.

In a strongly worded response to recent police criticism, Lynch questioned the attention Sharpton's received, alleging his only role was to "stir up" anti-police sentiment.

"I do not believe he has credibility. I believe he has an opinion," Lynch said. "He shouldn't have the right to sit at the lead table at City Hall and stir up the streets where it becomes dangerous for police officers.

"It's police officers you call when all goes wrong," Lynch added. "The only ones that'll dial Al Sharpton is someone that just got locked up with a gun and wants to be saved. The people that call the police are the folks that want to be saved from the man with the gun."

In his radio show, Sharpton said Lynch shouldn't try to make him the issue.

"What bothers me ... is that rather than deal with the issue they try to attack me, lie," Sharpton said. "And they've done it to every civil rights leader I've studied even far greater than me, try to mess with the messenger -- deal with the issue."

But Lynch said "pundits," like Sharpton, are proliferating an anti-police attitude, encouraging people to fight back.

"Now it is fashionable to resist arrest," he said.

Lynch then called the medical examiner's report, which determined Garner's death was a homicide, "political," alleging an absence of medical facts and promising to bring in experts to dispute the report.

"We will defend these police officers," Lynch said. "This was not a chokehold. We will get medical examiners to go over this autopsy when it is finally released."

Staten Island police tried to arrest Garner on July 17 for allegedly selling individual, untaxed cigarettes -- or "loosies." During the incident, which was caught on video, one of the officers placed Garner in a chokehold before bring him down to the ground.

Garner, who died shortly after, can be heard gasping on the video, "I can't breathe."

Lynch then went a step further, asserting that police officers feel they lack support from Mayor Bill de Blasio.

"It think the mayor needs to support New York City police officers. Unequivocally say it," Lynch said. "And unequivocally say resisting arrest hurts everyone -- police officers and citizens alike -- and it will not be tolerated. He needs to say it and he needs to say it forcefully. Police officers do not feel that they're getting the support that they need for the job that they do."

De Blasio called the city's medical examiner's office "the gold standard in this country" and said its "scientific" answers should be respected above all else. And for his part, he said, he wouldn't take criticism to heart.

"We have a job to do," de Blasio said at an unrelated news conference. "We're going to do our job. I don't let the rhetoric of union leaders stand in the way of getting the job done."

Police Commissioner Bill Bratton said criminality is ultimately up to the Staten Island district attorney.

"He's entitled to his opinion," Bratton said about Lynch at an unrelated event Tuesday. "Speaking on behalf of his members, he's entitled to defend them, to speak for them. I cannot criticize them. We have differences in opinion from time to time. Certainly, that's the nature of the relationship."

Ed Mullins, president of the Sergeants Benevolent Association, said selling individual cigarettes is not a "victimless crime."

"We don't get to pick the laws, we enforce them," he said.

Mullins said going forward all officers should slow down and follow the rule book, regardless of any potential delay in getting to the next call.

"I'm instructing ever sergeant out there to supervise each and every arrest the way our patrol guide is designed," he said. "And we'll move on to job by job as it happens."

(with Matthew Chayes and Emily Ngo)