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De Blasio was delivering his opening statement when the chants started up from the audience.
The chants continued after he finished.
Booker, too, was faced with them, and he ceased speaking as they carried on.
Members of the audience were talking about Daniel Pantaleo, a New York police officer who placed Eric Garner in a chokehold as he sold untaxed cigarettes on Staten Island, in an incident that was captured on video in 2014.
Garner exclaimed “I can’t breathe” 11 times before he lost consciousness and died later.
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Earlier this month — two days before the fifth anniversary of Garner’s death — U.S. Attorney General William Barr announced that the Department of Justice would not bring criminal charges against Pantaleo.
In doing so, Barr did not follow a recommendation by civil rights prosecutors from Washington who wanted criminal charges filed against the officer.
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Barr instead followed prosecutors in Brooklyn who said there wasn’t enough evidence to support a case.
“Even if we could prove that Officer Pantaleo’s hold of Mr. Garner constituted unreasonable force, we would still have to prove beyond a reasonable doubt that Officer Pantaleo acted willfully in violation of the law,” Richard Donoghue, U.S. attorney for the Eastern District of New York, said in mid-July.
Pantaleo has not been fired from the NYPD despite calls for his dismissal. He currently works on desk duty for the police force.
He has, however, faced a disciplinary hearing, a process through which an administrative judge will come to a verdict and send it to NYPD Commissioner James O’Neill, The New York Times reported.
The commissioner will then decide whether to discipline or fire him.
De Blasio has not moved to fire Pantaleo, nor has he said whether the officer should lose his job, CBS News reported.
Fellow Democratic candidate Julian Castro challenged De Blasio over Pantaleo during the debate. The New York mayor responded that the city was “changing fundamentally how we police” after Garner’s death.
De Blasio’s Twitter account also issued a series of tweets following the chants.
In one of them, he said, “While I believe that respecting the process is the best way to get justice for Eric Garner’s family, I recognize and identify with the pain people across this country are feeling.”
Booker’s account also tweeted during the debate.
The account praised the protesters for “standing up to Mayor de Blasio.”
New York Sen. Kirsten Gillibrand, meanwhile, said Pantaleo “should be fired now.”
- With files from The Associated Press