GWEN IFILL: The uproar over another grand jury's decision not to indict is making itself felt coast to coast.We start in Staten Island, where Eric Garner lived and died, and where members of the grand jury reside. The borough is also home to many of the city's police officers and firefighters.

NewsHour correspondent William Brangham takes us there.

WILLIAM BRANGHAM: While protests of outrage emerge across the country, and in different parts of New York City, Staten Island, where Eric Garner died, is relatively quiet. That's because this borough of nearly half-a-million residents is not like the rest of New York.

James Cohen teaches criminal law at Fordham University in New York.

JAMES COHEN, Fordham University Law School: Staten Island is part of New York City, but in many respects it is unlike the other boroughs. It is the most conservative of the five boroughs. It is the most demographically the same. It matters because the grand jury will consist of those people as well.

WILLIAM BRANGHAM: Staten Island is also home to a large percentage of New York's active and retired firefighters and police officers. And having those public servants as friends and neighbors might influence how people here feel about police and the Garner case compared to the rest of the city.

According to a recent Quinnipiac poll, while only half of New Yorkers approve of overall police performance in New York, nearly 80 percent of Staten Islanders do. In the Garner case, 65 percent of New Yorkers felt there was — quote — “no excuse for the police action” seen in that video, but only 45 percent of Staten Islanders felt that way.

When asked whether criminal charges should've been brought against the police for Garner's death, 65 percent of New Yorkers supported the idea, but only 42 percent of Staten Islanders did.

In our day spent reporting on Staten Island, we couldn't get anyone who supported the grand jury's decision to speak with us on camera, but we found several who were not happy with the decision.

WILL GRAHAM, New York: I would think that, you know, justice will prevail if we could see what is going on. Like, we actually have him on tape doing an illegal maneuver, and he still gets off. Like, it seems like that the cops have almost like a cloak of invincibility now, that the justice system is giving them that.

KARL WILLIAMS, New York: It like license to kill. Like, I don't understand how it's, like, possible for that to even happen. Like, remove the badge, you're a human being. You should be charged just as much as anyone else.

WILLIAM BRANGHAM: The Staten Island district attorney, Daniel Donovan Jr., who is up for reelection next year, stated that he conducted a thorough investigation into Garner's death and presented that evidence to the grand jury.

In a statement released yesterday, he said — quote — “I assured the public that I was committed to a fair, thorough and responsible investigation into Mr. Garner's death and that I would go wherever the evidence took me, without fear or favor.”

But according to Fordham's James Cohen, DAs, not just in Staten Island, but across the U.S., are too close with their local police forces and prosecutors have a conflict of interest trying to fairly judge police behavior.

JAMES COHEN: There is something incestuous, in a way, about that, and that is a principal explanation for why these cases ended up with no true bill, no indictment.

PATRICK PARROTTA, Criminal Defense Attorney: Jurors usually get it right. And you have to be in the system a lot to see it, but it does work. It does work.

JAMES COHEN: Staten Island defense attorney Patrick Parrotta says he believes the system works fairly. He says he has seen instances where police officers do get punished for wrongdoing. But, according to him, the Garner case just wasn't one of them.

PATRICK PARROTTA: These cases that evoke a lot of emotional response are very difficult. And the result of them is certainly unpredictable sometimes, and sometimes unpalatable, the result. But I haven't lost faith in the system.