Leading the nation’s largest police force is one of the most coveted jobs in law enforcement, a top position that for now is staying within the department's top ranks.

"It's my pleasure to introduce to you the next police commissioner of the City of New York, Dermot Shea," de Blasio said Monday during an announcement at City Hall.

In need of a replacement, Mayor de Blasio, once again looked within the department, naming Shea, a 28-year veteran of the force as the city's top cop.

Leading a force of 36,000 currently in the midst of several challenges even as the city’s crime rate continues to be the lowest in decades.

“We know where we’ve come from and what we’ve accomplished the last six years but there’s so much – in my opinion, there’s just so much more to do," She said.

Following his picks of James O’Neill and Bill Bratton before him, once again, the mayor named a white man to lead a department becoming more and more diverse by the day. The department's most recent recruits reflect the diversity of the city, but its top brass is still mostly white men.

Councilman Donovan Richards, chair of the public safety committee said the administration missed an opportunity to name a person of color.

"I think there are a lot of talented individuals in the department that should have ascended to this position, people who look like the department and where the department is going, so I think there was a missed opportunity here without a doubt," Richards said.

De Blasio dismissed the criticism; pointing to the department’s accomplishments as proof his choices for leadership have yielded results.

“I started watching Dermot in action six years ago. And watched consistently in strategy meetings, in press conferences, you name it. And I became convinced a long time ago that he was the future of the NYPD. So, it’s a simple as that," de Blasio said. "I think in the next few years you’re going to see a lot of leadership elevated that represent the full diversity of New York City.”

Shea’s appointment was met with criticism from criminal justice reform advocates, including the Rev Al. Sharpton, who called on Shea to hold a meeting with civil rights leaders to discuss policing tactics still disproportionally affecting New Yorkers of color.

Tina Luongo, Attorney-In-Charge of the Criminal Defense Practice at The Legal Aid Society criticized the new appointment.

“It feels like an inside game. We live in the most diverse city in the country, we have been calling for the diversity of perspective and lived experiences in the leadership and here we are again, no input no transparency and no real true vision for what a police department in New York City should be and could be,” Luongo said.

De Blasio’s relationship with the department’s rank and file has been strained since he was elected on a platform of police reform. He is hoping the appointment of Shea will lead to steady leadership for a department facing multiple internal challenges.

Michael Palladino, president of the Detectives Endowment Association said Shea has big challenges ahead.

"Morale is down I think it shows in the amount of suicides, the attacks on police while they're trying to perform their duty, it doesn’t really help a lot," Palladino said. "I think also crime is starting to tick up a little bit, shootings and homicides, so it's not an easy job. He comes in at a time where he's going to have to make some changes quickly."

Despite being elected on a platform of police reform, de Blasio has stuck with the NYPD’s inner circle for leadership. A new set of challenges is just around the corner; criminal justice reforms take effect next year. Shea's first day on the job is December 1st.