NYPD Police Commissioner Bill Bratton will retire in September, leaving behind a team to further the department's policy of neighborhood policing that has been a key element of his 31 months as commissioner. 

On Tuesday, Mayor Bill de Blasio announced that Bratton will retire from his position next month and be replaced by current Chief of Department Jimmy O’Neill, an NYPD veteran with more than 30 years of experience who began his career patrolling the A and D trains during overnight hours. 

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"As the architect of our neighborhood policing program, Jimmy O’Neill has built a national model for bringing police and the community together to fight crime," de Blasio said. "Our next police commissioner's decades of experience make him uniquely qualified to continue building on these incredible public safety achievements."

The mayor and Bratton indicated that the commissioner's retirement stems from a separate offer that he has received and good timing for him to transition into a new role that will benefit his future, although the details of that role were not given at an afternoon news conference. Both officials stated that his departure had nothing to do with any NYPD-related corruption scandals or protests about the department. 

"I cannot thank the mayor enough for his confidence in this team," Bratton said of de Blasio, complimenting the mayor for his support of the NYPD during his time as commissioner, adding that the police were able to "redefine our role from being the police to being your police." 

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New York's police department shifted toward a more community-oriented, neighborhood policing strategy under Bratton's leadership, a trend that de Blasio said would be in place in 51 percent of precincts and 100 percent of public housing commands starting this fall.