One night in November 2015, a man entered a fast-food restaurant in downtown Camden, N.J., and threatened employees and customers with a knife. When police caught up with him, he was walking down a nearby street, swinging the knife in his right hand. He repeatedly ignored their commands to drop the knife and kept walking. The officers walked with him, closing off sidewalks and streets, securing buildings and trying to initiate dialogue. At one point an officer deployed his Taser, but the device was ineffective. After several blocks, the man turned a corner, slipped and dropped his knife. Officers quickly and safely brought him into custody.

Camden County Police Chief Scott Thomson was blunt in his assessment of the encounter, which was captured on video. "Six months ago, we would have shot that individual," he said.

Thomson had initiated sweeping changes in Camden's policing, trying to minimize the use of force by officers and emphasize the "sanctity of life." Under the new regime, complaints alleging excessive force by the department plummeted, from 65 in 2014 to 16 last year.

Such experiences offer hope that police and sheriffs' departments willing to embrace a major cultural shift can reduce the number of incidents in which officers use deadly force.

For far too long, agencies have held on to the notion that officers should never back down. Police avoided second-guessing each other's actions. And officers were told that their No. 1 priority should be getting home safely at the end of each shift. But departments that instill the importance of de-escalating situations, that are willing to acknowledge and learn from their mistakes, and that strive to get everyone through the day alive can, in fact, prevent citizens from being shot.

The success in Camden and elsewhere isn't yet reflected in national statistics. The Washington Post reported that police officers in the United States shot and killed nearly 1,000 people in 2017. Unfortunately, that total has not changed much since The Post began gathering these statistics in 2015, after the shooting death of Michael Brown in Ferguson, Mo., the previous year precipitated intense scrutiny of police use of force nationwide.

Those numbers are stubborn in part because, in a country with more than 300 million firearms in private possession, officers regularly face dangerous situations involving people who are armed. According to The Post's analysis, approximately 60 percent of the individuals shot to death by police in each of the past three years had a gun. In those types of situations, police officers have limited options; they must focus on protecting public safety and their own safety.

However, a shift in approach could have a significant impact on the remaining 40 percent of cases — close to 400 per year — in which the subject does not have a firearm. Many of those cases involve people with mental illness, according to The Post.

Changing police culture requires providing officers with clear, strong policies. In 1972, New York City police officers fired hundreds of shots at suspects, some of whom were in moving vehicles and not firing on officers or otherwise using deadly force. In one incident, a 10-year-old boy who had been a passenger in a stolen car was shot and killed by police. That year, the NYPD changed its policies to prohibit officers from shooting at moving vehicles in most instances. Thanks to that and other reforms, officer-involved shootings quickly plummeted and have continued to decline. In 2017, the NYPD — a department with more than 36,000 officers — had only 23 incidents in which officers fired a shot at a suspect.

To carry out good policies, police officers need adequate training — and continuing retraining to reinforce what they have learned. But many agencies, if they provide any specialized training at all, follow the same curricula they have used for decades. Too often, that training is presented in silos: Officers attend a class on how to recognize someone in a mental health crisis, then, weeks later, they learn communications skills and tactics in separate courses.

Newer training regimens — such as the one developed by the Police Executive Research Forum — integrate these skills and have officers practice them in scenario-based exercises.

And departments are starting to see results. For example, in Baltimore, where training was overhauled in the face of a Justice Department investigation, the police department saw excessive-force complaints drop by 36 percent in 2016 and a further 42 percent in 2017. During one episode captured on body camera last September, a distraught man with a knife urged Baltimore officers to shoot him. But officers kept their distance, patiently talking to him and establishing rapport. "I can relate to you, bro," said Officer Angel Villaronga. ". . . At the end of the day, I've got kids to go home to." The man surrendered his weapon.

In New Orleans, the police department is training its sworn personnel in how to spot a fellow officer who may be on the brink of using excessive force and to intervene before things get out of control. A formal evaluation of the training is underway, but officials report anecdotally that over the past two years there have been several successful peer interventions.

Police chiefs can reinforce policies and training by recognizing and rewarding officers who display professionalism and restraint. For example, the Los Angeles Police Department created a "Preservation of Life" award for officers who safely defuse an incident without the use of deadly force, even when such force might have been legally justified. Philadelphia police established a similar award.

Some agencies also are moving away from the notion that they should not analyze or question the decisions of officers, beyond the standard legal and administrative reviews. After officers in New York City and Burlington, Vt., were involved in fatal use-of-force incidents in 2016, the leaders of both of those agencies publicly acknowledged failure and vowed to improve. That would not have happened years ago.

Many of these changes are taking place in agencies led by progressive police chiefs and sheriffs. But policing in America is highly decentralized, with more than 18,000 individual agencies. Progress will be uneven without a national commitment to change.

The federal government can play an important role here. We know that agencies need help with policies, training, leadership development and best practices. The federal government can help fund training and technical assistance in these areas.

Preventing officer-involved shootings is a monumental task. But when all of the pieces are in place — sound policies, effective training, leadership and culture change — agencies can see positive results.

The late John Timoney, a legend in the policing profession from his days in New York City and Philadelphia, taught us that lesson 15 years ago when he became police chief in Miami. In the decade before Timoney arrived, officers there had discharged their firearms at more than 150 civilians, killing two dozen of them. The Justice Department was investigating a pattern and practice of excessive force.

Timoney implemented sweeping reforms that included new use-of-force policies and training. He attended roll calls and personally explained the changes to his officers. He recognized officers who showed courage and self-control in tense situations. In short, he began to change the culture of the agency, and his impact was remarkable: Miami experienced periods of 20 consecutive months, and then 12 months, without a single police officer firing a single shot.

These leadership principles are timeless. It is time for all American police leaders to embrace them.

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