On Tuesday in New York City, thousands of police officers will walk solemnly into St. Patrick’s Cathedral to pay their respects to one of America’s most revered police leaders. John Francis Timoney died last Wednesday after a brief battle with cancer at age 68. It was the only fight that this brilliant, iconoclastic, wonderful person ever lost.

John was a Dublin native who immigrated to America with his family at 13. After the death of his father his mother decided to return home, but John, then 17, stayed along with his brother. America should be glad he did. He went on to become one of our greatest cops, named “America’s Best Cop” by Esquire Magazine.

He was Deputy Commissioner in New York, Police Chief in Philadelphia, Miami and called America’s best cop by Esquire Magazine. Wherever John went crime fell – and drastically. What greater tribute can we pay than that simple fact.

John was a man of great intellect and character who was comfortable with everyone – patrol cops, mayors and political leaders, intellectuals like the writer Tom Wolfe, downtrodden people on the streets – John could connect with them all. And he was welcome everywhere, from a Knights of Columbus hall in the Bronx to Elaine’s restaurant on the Upper East Side.

Read more: John Timoney, Irish American policing legend, passes from lung cancer

Everyone knew that John was born in Dublin and spent most of his childhood there. His family moved to New York in 1961, and John spent his teenage years there. His father Ciarán died while John was in high school, and John’s mother and sister moved back to Ireland after John finished high school. But John and his brother stayed in New York, sharing an apartment and supporting themselves. John became a police officer in the largest department in the United States, the NYPD.

John rose quickly through the ranks, and was named first deputy commissioner – the number-two person in the entire department – when he was only 46. It was William Bratton, one of the most highly regarded police chiefs in U.S. history, who recognized John’s talents and gave him this promotion. Bratton and Timoney were a great team in the NYPD. Bratton was the forward-thinking reformer from Boston, and John was the NYPD “insider” who had leapfrogged to the top. Together, they took the NYPD forward.

John’s brilliant career has been well-documented, both in New York and later in Philadelphia and Miami, where he served as the top police official.

I would like to share my perspective about John, as someone who knew him for 20 years, and as the executive director of a “think tank” that identifies best practices and policies in policing.

My perspective is that John was decades ahead of his time. Here is what I mean. Today, police agencies in the United States are facing unprecedented challenges. Controversial uses of force by police, and strained relationships in many cities between the police and communities of color, have put police under the microscope.

Fortunately, the best and brightest police chiefs today are finding ways to make needed reforms. And what is striking to me is that many of the “new” policies that are being implemented today are not really new. They were developed decades ago by John Timoney.

For example, many police agencies today still allow officers to shoot at moving vehicles. This is a policy that makes little sense, because even if the officer is able to shoot the driver, it doesn’t help to have a mortally wounded person behind the wheel of a speeding car. So back in 1972, John Timoney helped implement a tight ban on that practice in the NYPD. This was a key element in a package of reforms that cut the number of police shootings almost in half, from 994 in 1972 to 526 in 1974. These shootings continued to decline, to fewer than 100 per year in recent years.

Later, John became chief of police in Miami in 2003, at a time when 13 Miami officers were being prosecuted on charges resulting from shootings of civilians. He implemented new policies, training, and equipment, and the change was immediate: 20 months without a single police shooting in Miami.

Weak investigations of sexual assaults are another issue that continue to make headlines across the United States. Back in 1999, when John was commissioner of police in Philadelphia, he took the unprecedented step of allowing leaders of women’s organizations to review case files alongside detectives, in order to gain important new perspectives on ways to improve investigations. Today this is considered a model practice that builds accountability and public trust.

Another reform that is being discussed a lot these days is creating policies establishing a “duty to intervene.” The idea is that when an officer witnesses a fellow officer engaging in misconduct or looking like he is about to lose control, the officer should be required by policy to step in and intervene.

Many departments today have no such policy, even though it’s an excellent idea that dates back to 1993 for John Timoney and the NYPD. John recently described how it came about:

“The Rodney King incident had just happened in Los Angeles, and the video showed more than a dozen officers standing by and watching the beating happen. For many of us seeing the sergeant at the scene watch passively violated every principle of proper supervision. So we wrote a policy for the NYPD creating a duty to intervene.”

A duty to intervene policy not only prevents misconduct; it helps save officers’ careers. Here is how John explained it to his fellow police chiefs, earlier this year:

“Sometimes, in the heat of battle, a cop loses his cool. It’s never an excuse for using excessive force, but it happens. But it can be prevented if other officers step in at the first sign that another officer is losing control of himself. That’s what a duty-to-intervene policy is about.”

Because racial issues are central to the strife in American policing today, I should mention that John Timoney spoke plainly and directly about racial justice. In the late 1990s, the organization I direct convened a national meeting of police chiefs following a controversial police shooting of an African-American man. When the meeting ended, we were trying to craft a statement of consensus, summarizing what we had learned from each other. I remember that John read a draft of a statement, and told us, “This doesn’t say anything. We have to say that race matters. That is the reality. When a police chief gets a call in the middle of the night about a police shooting, the first thing he asks is, ‘What is the race of the officer, and what is the race of the person who was shot?’ Race matters, and we need to admit it.”

There are many other examples I could mention, but it all adds up to this: in the year 2016, thousands of American police agencies would do well to adopt policies that were advanced by John Timoney and his colleagues decades ago, and which have proved successful for all these years in the departments that John led.

I also want to mention that John loved to tell stories, and he had good ones about his adventures as a young cop in the Bronx. John had presence. He could light up a room when he walked in. His face captivated everybody, and he had a great sense of humor. We’ll never forget the Timoney sayings, like “He had an ego that could choke a horse,” or someone was “a bird of rare plumage.”

But his forte was good old common sense and how to impart it to cops.

He once noted, “There’s a fine line between disorderly conduct and freedom of speech. It can get tough out there, but I tell my officers, ‘Don’t make matters worse by throwing handcuffs on someone. Bite your tongue and just leave.’ ”

And there were Timoney rules for police chiefs, like this classic: “Any time something big happens, the first information you get is always wrong. And cops always want to tell you what they think you want to hear. So if you’re having a problem getting information, it means there’s a problem with the information!”

The policing profession in the United States is saddened by the death of John Timoney. He is held in such high regard here because he personifies what we all think of when we think of a good cop: he was courageous, thoughtful, and had a good heart. And he knew how to get things done. He successfully pushed American policing to do what is morally right, not just what is legally required.

There are thousands of people like me who will miss him and think of him often.

* Chuck Wexler is executive director of the Police Executive Research Forum (PERF), a Washington, D.C.-based organization whose mission is to research and develop best practices in policing.