Here's who will take over as NYPD Commissioner when Bill Bratton leaves
O'Neill has become a leader in the movement to reduce tension between police departments and minority communities. As Chief, he will command the country's largest police force.
Bratton told the Wall Street Journal that he appointed O'Neill to Chief of Department because of his skills in communicating with both officers and citizens. Shortly after he began the job, protests erupted over the killing of Michael Brown in Ferguson, and two officers were shot in Brooklyn.
"Right from the onset, the weight was tremendous," O'Neill told the Wall Street Journal in July.
Under O'Neill, the department has begun to adopt a new model throughout many of its precincts in which officers are evaluated based on how effectively they reduce crime conditions, not the number of arrests they make, reports the Journal. Officers are asked to set aside time in their shifts to built relations with the community.
O'Neill will assume his new role in September. He will be succeeded as chief of department by Carlos Gomez, currently chief of patrol.
O'Neill's career is not with blemishes. In 2008, while he was chief of the department's narcotics division, he was transferred out of the unit when a group of officers was caught paying informants with drugs, according to The New York Times.
But Bratton, who announced he would step down from his position Tuesday, has praised O'Neill repeatedly. He hinted in July that O'Neill was a serious candidate to take over his own job when he left.
"Basically what I have worked on all these months is giving the mayor the options when I leave to pick someone in the department," Bratton said in an interview with the Wall Street Journal. "Jimmy would certainly be one of them ... he has a full understanding that to be successful at crime reduction you need cooperation with the public."
Even before Bratton announced his pick, the leaders of police organizations reacted positively to the possibility of O'Neill as Commissioner.
"He's a solid guy," Roy Richter, president of the Captains Endowment Association, told the New York Daily News. "He would be a good selection if that's who the mayor chooses and if the position becomes open."
Lou Turco, president of the Lieutenants Benevolent Association, agreed.
"He'd be an excellent choice to be a police commissioner," he told the Daily News. "He's a cop's cop - 100%."