O'Neill said he made that decision alone, calling it "one of the most difficult things" he's had to do.
As for the Patrolmen's Benevolent Association call for a work slowdown and a no-confidence vote agains the mayor and police commissioner, O'Neill was cautious.
"(PBA President) Patty Lynch is doing what he thinks he should do for the membership," he said. "But he needs to be careful not to destroy their confidence."
Asked about speculation that he would soon leave his job, O'Neill responded, "I don't know why I would do that. My heart and soul is with the NYPD.... Unfortunately, many jobs run on rumors."
Carr said that the decision to fire Pantaleo did not provide a sense of justice, but "a sense of going in the right direction."
Carr said Mayor Bill de Blasio should have acted sooner rather than wait for the case to go through the courts or the federal government to act.
"I wanted the NYPD to take a stand," she said. "It was recommended for charges (against) Pantaleo since January 2015 and nothing was done. This is where my anger came in. Why are you just sitting back?" she said in her first interview on local television.
Joining her in the interview was an outspoken advocate in the Eric Garner case, Rev. Kirsten John Foy.
Also on Up Close, a look at the week in politics, including President Trump's various policy pronouncements via Twitter.
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