New York Police Commissioner William J. Bratton unexpectedly announced his resignation Tuesday for a position in the private sector and will step down in September. Mayor Bill de Blasio immediately announced NYPD Chief of Department James O'Neill as Bratton's successor. 

Bratton is leaving behind quite a legacy in policing in a career that spans more than 45 years in law enforcement in major cities including Boston and Los Angeles. He has become one of the most recognized commissioners across the country and has been a force in changing the dynamic between police officers and community members during his tenure.

"I don't think anyone could've imagined a more productive 31 months. We will never forget or fail to honor the achievements of Bill Bratton," de Blasio said. 

O'Neill, who will serve as New York's 38th police commissioner, takes over after a prestigious career. Bratton said that O'Neill "has brought police and the people together" and "has all it takes to lead the NYPD into the future." 

"I love being a cop. I love this uniform. I love what it stands for," O'Neill said. "We are here for you, the people of this city." 

Check out a few interesting facts about the newest NYPD Commissioner below.

1. O’Neill has been with the NYPD for over 30 years: He was appointed to the New York City Transit Police department in January 1983. Starting out on patrol in Transit District 1, O’Neill was later promoted to Sergeant in 1987 and has since held positions as Sergeant Special Assignment, Lieutenant, Lieutenant Special Assignment, Captain, Deputy Inspector, Inspector, Deputy Chief and Chief of Patrol. He has served as commanding officer of the 25, 44 and Central Park Precincts.

2. He’s passionate about alleviating tension between police and residents in New York City: One of the new commissioner’s strong suits, according to Bratton, is his impeccable ability to create clear lines of communication with both residents and fellow officers. O’Neill has also been a force driving better relations between officers and residents by encouraging on-duty cops to get out of their cars and talk to residents instead “rolling up on people” in their cars. Because of his efforts harsh police tactics like “stop and frisk” have steadily been on the decline.

3. His policing programs may have landed him his new position: Another method of creating better communication between cops and residents has been O’Neill's newest strategy to evaluate officers on how they handle eradicating crime as opposed to the number of arrests they make. Under O’Neill’s leadership, officers have also been instructed to take time during their shifts to develop relationships with the people living and working in the areas they’re patrolling. In an interview with NY Daily News, Bratton spoke highly of the programs O’Neill has developed and even said O’Neill reminded him of the work he used to do back on Boston’s force, stating, “A lot of what Jimmy is implementing now, here, is in many respects what I implemented back then. And it worked back then.”

4. He almost left the force to join a private sector earlier in his career: Back in 2008, when O’Neill was the head of the narcotics division, he almost left his post after three officers in his division were caught paying informants with drugs, which resulted in O’Neill’s transfer to the fugitive enforcement division. He nearly gave up on the position in 2013 and started questioning Bratton about jobs in the private sector. However, after a little encouragement, Bratton managed to convince O’Neill to keep his post and shortly after O’Neill was asked to join Bratton’s executive staff when he was made commissioner under de Blasio.

5. He’s highly educated: O’Neill has a bachelor’s degree and a master’s degree from the John Jay College of Criminal Justice.