Charting the history of policing in America, the new documentary “Power” is rooted in questions: Who exactly are the police meant to serve? And whose interests are they protecting? Utilizing an essay form, the film turns to an impressive roster of legal experts, scholars, journalists and law-enforcement officials to bring the viewer along for an inquisitive probing of an issue that cuts to the core of social divides.

When director Yance Ford’s 2017 film “Strong Island” was nominated for an Oscar for documentary feature, it made him the first openly transgender director to have a film nominated for an Academy Award.

“Strong Island” examines the story of how Ford’s brother William, then a 24-year-old teacher, was shot to death by a white 19-year-old mechanic in 1992 in an incident a grand jury found justifiable. The film explores in intimate detail the impact the criminal justice system has on one family’s grief.

With “Power,” Ford takes on a much broader scope, while still grounding the documentary very much in personal inquiry and curiosity. The core missions of police to protect property and control populations are often at odds with public safety and community concerns. Though the film does not provide easy answers, it does point in the direction of what could be done to make relations between police and citizens less oppositional.

“This film is a tool for people who do this work,” said Ford, 52, during a recent interview. “I hoped that it would be something that people who work to reimagine our definition of public safety can use.”

“Power,” which premiered earlier this year at the Sundance Film Festival, is now streaming on Netflix.

This interview with Ford has been edited for clarity and length.

Q: “Strong Island” was such a personal film, exploring your family’s experience with the criminal justice system. Did “Power” come out of an attempt to get a 10,000-foot view on what you had gone through?

A: In many ways, I’ve been thinking about policing since there were detectives in my parents’ house explaining to them why the person who killed my brother wasn’t going to be charged with a crime. But when George Floyd was murdered and the protests were happening in the aftermath, I saw and felt something different in the reaction of police to the protests around the country. And in the city where I live, New York, that felt different. It felt dangerous. It felt unrestrained. And it felt like there had been a shift. This feeling got me asking the question, “Is this what police are for?” in a way that felt different than the times I had asked that question in the past. These were police acting as an occupying force and acting, quite frankly, as the armies that they have become. And that’s what started the line of questioning that turned into the film. It was less about the 10,000-foot view of what my family had gone through and more about what I was seeing play out on the streets in the United States and around the world.

Q: The film begins with a statement from you in which you say, “This film requires curiosity, or at least suspicion.” Can you expand on that?

A: I put that at the top of the film because I know that this subject of policing is one where the current debate has been Black Lives Matter (or) Blue Lives Matter. Whenever policing is brought up as an “issue,” there are folks who will think that a documentary will be a polemic against the police or that a documentary will be something that reinforces their own analysis of policing. And what I wanted to do was invite the audience, regardless of where they sit in relation to this issue, to come to the film as they are.

Q: One of the most surprising characters in the film is Charlie Adams, the Minneapolis police officer working to reform policing from within the institution itself. How did you come to find Charlie Adams?

A: We researched a lot of different police officers, police commanders, police chiefs around the country who were doing work in their departments. And Charlie Adams rose to a place on the list that was interesting to us because he is in Minneapolis, and he’s been doing work for a long time trying to help his officers at the 4th Precinct understand the perspective of the community and the people who live in the community in which they serve. Charlie Adams is a great character because he is someone who you see has good intentions, but he’s also someone who is restricted by the contours of the institution in which he works. There are aspects of the criminal legal system that limit the effectiveness of what he can do. I think that Charlie Adams tries to do what he can, but then when you see this thing where he butts up against the reality of policing, that helps you understand that it has to be about more than individual chiefs or individual officers.

Q: There’s a moment in the film when you say to an interview subject that you want to address this idea of the “we-ness of it all.” Is that one of the challenges in talking about policing? Is it difficult to address the issues and concerns of all these separate communities, different people, different sets of “we”?

A: “Who is the ‘we,’ ” in my view, relates directly to the question at the end of the film about power conceding nothing without a demand. Because knowing who the “we” is is a part of defining what the demand will be. What demand are you going to make of police? What demand am I going to make of police? As soon as we get specific about who the we is, then we can drill down and understand what we will demand of policing. Because for too long the people whose job it is to regulate police, to tell police what their job is and how to do their job, they’ve walked away from it or they’ve left it up to police to be this self-regulating industry.

Q: Why did you choose to call the film “Power” as opposed to simply calling it “Police”?

A: Because they’re synonyms — they are one and the same. Police are the power of the state made real. You and I and other people, some more so than you and I, will interact with police way more often than they will interact with their elected representative or senator. So in terms of how the government and the state is made manifest in people’s lives, the answer to that is police. When you think about who is the most powerful person, like (journalist) Wes Lowery says, in this country, on a day-to-day basis, it’s police for most people. And so I wanted to just be really clear about the lens through which the film is going to look at police and policing. And it’s also just a great title, if I do say so myself. It tells you what you’re going to see. When you buy a ticket to a film called “Power,” you’ve got a sense of what you’re in for.