The old boss will be the new boss once again. Former New York City police commissioner Bill Bratton has been tapped to be the next police commissioner.

Bratton headed the police force in Los Angeles in between his stints in the Big Apple. His is one of a handful of names on the perpetual short list for big city police chiefs.

“We usually look at a handful of individuals. And sort of move them from one place to another,” says Maki Haberfeld, a professor at the John Jay College of Criminal Justice.

She has written books on police leadership, and has met lots of promising leadership candidates. Haberfeld says, “There are females. There are minorities. The list is long.”

But if the list of good candidates is so long, why do the job searches focus on just a few names?

“It’s all about the political connections,” says Haberfeld.

In the most political of cities — Washington DC — a woman is chief of police. But that’s just one city.

“Unfortunately, we are still very much behind other professions, including the military,” says Haberfeld.

Others believe the list for a new police chief is short because there aren’t many qualified candidates.

“So the population of people who might go for a job like New York are probably only coming from about 200 large police departments across the country,” says Jack Greene, a criminal justice professor at Northeastern University.

Even if candidates have the leadership and law enforcement skills, they may not have the political savvy. Or they might not want to move to another city. Or, they may fear that moving will risk their current pensions.

As a result, Greene says, “There are only a handful of people who have really-big city police experience.”

And while politics can be a factor in who gets the job, political savvy is also a job requirement.

“Police commissioners, police chiefs, have to have a pretty strong ego, and a pretty large ego, because there’s almost a crisis du jour in these places that have to be managed and have to be dealt with both administratively, but also politically.”