On a rainy fall day in Washington, DC, Chuck Wexler, PhD ’84, is running a session at the US Department of Justice. As executive director of the Police Executive Research Forum (PERF), he’s attempting to draw ideas from a group of law enforcement officers, forensic scientists, and public health professionals about how to train police as they confront the country’s escalating opioid crisis. He quickly wades into controversial terrain.

The subject turns to “safe injection sites”—places where users can inject drugs under the supervision of medical staff. “Has there been research?” Wexler asks. “Has this been evaluated, or is this something you do out of desperation? Has it reduced overdose deaths?” An attendee from Vancouver, BC, says the data show that the sites dramatically lower overdose rates.

Wexler nods. Several US police departments are contemplating the strategy, but it is illegal under federal law, and the Trump administration has promised a crackdown.

“I know too many parents who lost their children to drug overdoses,” Wexler says, adding that they would probably be alive if they’d had access to such facilities. “We can’t be afraid to look at other countries that have had success.”

For decades, Wexler has tackled the most pressing, intractable challenges in policing, and he has ventured beyond US borders and outside law enforcement for answers. He’s a civilian who’s managed to earn the respect—sometimes grudging—of a profession bound by insularity and tradition. Since he took the lead at PERF in 1993, the organization has become a globally regarded resource for police executives confronting a range of emerging or stubborn problems.

“Anytime a police chief is in a tough situation, invariably Chuck Wexler is their first phone call,” says Scott Thomson, chief of the Camden County Police Department in Camden, New Jersey, who sought help from Wexler when the city—among the most dangerous in the country—took the unusual step of disbanding its dysfunctional police department and replacing it with a county department. “He plays this very influential, behind-the-scenes role for police chiefs in America and in other countries.”

Wexler runs forums around the world; in 2012 he even got police chiefs from Israel and Palestine to meet for the first time. He is routinely called to troubled areas in the wake of conflict to smooth over relations between beleaguered police forces and an angry, edgy public. After the 2015 death of Freddie Gray in police custody, for example, Wexler went to Baltimore to hold a massive meeting. After a 2002 sniper rampage in the DC area, PERF issued a major report. “Mistakes get made,” Wexler says. “What we try to do is understand what happened and put it out in a way that people can learn from.” PERF’s management training program is now considered essential for any police executive who intends to lead a department.

“He totally transformed PERF into what it is today—a leading think tank on policing issues in the country and beyond,” says Charles Ramsey, a former PERF president who served as police chief in Washington, DC, and then as commissioner in Philadelphia. “He’s not afraid to tackle tough issues, and he’s got an instinct for seeing what’s on the horizon, not just dealing with the crisis of the moment but what’s coming down the pike.” The problems police face as they encounter more opioid users and increasingly violent confrontations are just a couple of examples that Wexler saw coming two or three years before they hit in a big way, Ramsey says.

In 2015, the year after widespread unrest following the fatal shooting by a police officer of Michael Brown in Ferguson, Missouri, Wexler took a group of police officials to Scotland to learn how officers there defuse violent confrontations. Though the US and the UK share many policing traditions, there is one major difference: the vast majority of police in the UK don’t carry firearms.

“We have so much in common with them, but we’re very different on use of force,” Wexler says. “We have 300 million [civilian] guns. They don’t.”

Wexler recalls meeting a young graduate of the police academy in a town near Edinburgh. He asked the officer how he was taught to cope with a violent suspect holding a knife. The man demonstrated his response.

“He just started backing up,” Wexler says. “And it hit me like a ton of bricks: why is it that they can do it that way and we have to kill people?”

According to a database assembled by the Washington Post, police officers fatally shot 995 people the year after the Ferguson riots. (The government does not track these shootings.) In 2016, the Post began tracking how many of those confrontations involved suspects holding knives, not guns; for each year since, that described between 16% and 18% of the encounters. Wexler saw an opportunity. If police in the United States could be trained to “de-escalate”—to back away—lives might be saved.

To identify best practices for resolving situations with people who don’t have guns, Wexler turned to research skills he honed while studying organizational change at MIT, where he says he learned to be rigorous and to apply controls even in settings where that’s difficult to do. “Sometimes it can be challenging doing research in policing,” he says. “MIT gave me a healthy skepticism about things.”

On the basis of that research—as well as years of work involving hundreds of police professionals, several national conferences, and field work in Scotland, Northern Ireland, and New York—PERF released its “30 Guiding Principles on Use of Force” in 2016. (The organization has published more than 130 guides, manuals, and other research-based reports since 1996.) The PERF 30 integrates elements of critical thinking, crisis intervention, and police tactics; an accompanying training program instructs officers to take a “tactical pause” when confronted with a person holding a weapon other than a firearm.

In theory, police are already trained to escalate or de-escalate as a situation develops, explains Roberto Fernandez, co-director of the PhD program in economic sociology at Sloan, who teaches in PERF’s management training program. “You’re supposed to be able to slide back and forth,” he says. “But when you have an encounter, in practice, you only slide one way. They never back up. Chuck is trying to get them to think of it as a cycle—to get them out of the mind-set that it only goes one way.”

The first principle of the PERF 30 is simple: “The sanctity of human life should be at the heart of everything an agency does.” But it is also controversial. Police departments have long operated with an implicit notion that in a violent confrontation, the most important thing is that the officer gets home safe that night. That mentality is enshrined in police policy and law.

In fact, when a draft of the PERF 30 first circulated in 2016, the Fraternal Order of Police, the International Association of Chiefs of Police, and major police unions denounced it, even as many of the largest police departments folded the principles into their own and initiated de-escalation training. Many smaller departments, which are typically more traditional, have not implemented PERF’s concepts. Wexler says they often lack the resources to do so—and some may not be aware of the recommendations.

“There are 18,000 police departments in the US. Seventy-five percent have 25 officers or less,” Wexler says. “We’ve developed something that’s unique in the field, but what keeps me up at night is getting 18,000 police departments to use it.”

Meanwhile, big-city police chiefs who have implemented the PERF 30 training say it’s working—and saving lives on the streets.

Thomson says it’s invaluable for front-line officers to get the training that was previously reserved for specialists such as SWAT and critical-incident teams. “They don’t have time to wait for a SWAT team to get there,” he says. “The training is providing more options to the first responders so they’re not in a situation where they feel like the only option is force.”

For Wexler, that’s especially gratifying. “These principles were so controversial,” he says. “Now I hear police say: ‘Six months ago, we would have shot the person, but we didn’t.’”

Wexler’s interest in policing is rooted in the 1960s, when clashes between civilians and police were shaping an era. He earned a master’s degree in criminology from Florida State University and moved back to his native Boston, securing an internship with the Boston Police Department. At the time, the department was handling the desegregation of the public schools, which triggered violence and protests across the city. The department’s role in keeping the peace struck Wexler profoundly.

“I came to see policing as a way to help,” he recalls. And he still does. On a wall at the PERF offices, there’s a photo of a police officer handing a homeless person a pair of boots. “There are all these people out on the streets, and if you think about it, the only person who knows about them or cares about them is a police officer,” he says. “Good policing is a recognition that it’s your responsibility to look out for these people.”

During his internship, he began to take courses at MIT, where his eventual dissertation in urban studies and planning focused on the police department’s role in desegregation. “It was the intersections of these two cultures—the Boston Police Department, this nitty-gritty, real-world environment, and MIT, where you’re always thinking and asking questions,” he says. “Somewhere in the middle, those cultures shaped my thinking.”

Wexler “was energetic and lively, and critical, but in a generous way,” recalls John Van Maanen, a Sloan professor of organization studies who had Wexler in his class on organizational change and now teaches in PERF’s management training program. “I didn’t teach a course that had right answers. It was controversial, so he fit right in.”

Though he’s got a doctorate, people rarely refer to him as Dr. Wexler. He’s just Chuck. And his low-key humility has helped earn the esteem of police officers. “I knew him for two or three years before I realized it was ‘Dr. Wexler,’” Ramsey says. “He’s not a guy that toots his own horn. He took a path that most people who come out of MIT don’t take.”

That path has sometimes put Wexler himself in harm’s way. In July 1979, an armed man barricaded himself in an apartment in a house in Boston’s Jamaica Plain, along with his family. The police superintendent asked Wexler—who had recently helped design the department’s hostage negotiation program—to come along. Together, they approached the house. “Pop, pop—right through the door,” Wexler says, recalling the moment the shots struck the superintendent. After the shooting, Wexler dragged the superintendent to safety with the help of another officer. He survived, and the department gave Wexler an award. “They’d walk through fire for him after that,” Fernandez says.

Still, he encounters a fair amount of pushback. When Wexler walks into a roomful of police executives, he’s usually met with a sea of (mostly) men crossing their arms. “They’re skeptical,” Van Maanen says. “They listen politely.”

That he isn’t a police officer probably doesn’t help, although it’s what enables him to think in ways that police typically don’t.

“He understands policing more than a lot of police do, but he doesn’t carry the baggage,” Ramsey says. “He’s not locked into anything. He’s always asking why, and that keeps him moving forward.”

At his office on a recent Saturday—he works most of them—Wexler is wearing a sweatshirt that reads “Wellfleet Oysters,” surrounded by pictures of himself with foreign dignitaries and US presidents. “I’m the kind of boss who likes to be interrupted,” he says. “Saturdays are my days for concentration, reflection, and preparation.” At 68, he does not appear to be eyeballing retirement anytime soon.

PERF recently published another report on strategies to reduce gun violence, based in part on a “teach-in” Wexler conducted in June with officers from around the country to discuss everything from everyday gun crimes involving gangs and drugs to mass shootings, domestic violence, and suicide. On the horizon now is the next big challenge: getting more young police officers into the force. In December, PERF held a forum of police chiefs, officers, and human resources professionals to discuss the precipitous decline in applications to police departments and the difficulty of retaining new officers.

“When you ask a parent if they want their kid to become a cop, no one says yes,” he says. “But we need more good police. When you’re in a crisis, there’s nothing better than a good cop and nothing worse than a bad cop. If we can help with that, that’s important.”