If you grew up in New York City in the 1970s, the number can be hard to get your head around: 291. If you were a reporter in New York City in the early 1990s, the number can almost make your head explode: 291 murders in 2017, the lowest total since the 1950s.

But the number is perhaps most striking when set not against the numbers of murders in other years, but against this figure: the roughly 10,000 police stops conducted in 2017.

The longstanding rationale for the New York Police Department’s widespread use of what came to be known as stop-and-frisk — encounters between officers and people they suspected of suspicious behavior — had been that it was an essential crime-fighting tool. Such stops got guns off the street, the theory went, and low-level enforcement helped sweep up criminals destined to commit more serious crimes.

Former New York City Mayor Michael Bloomberg speaks at a press conference with former New York Police Department Commissioner Ray Kelly to address the NYPD's stop-and-frisk practice on Aug. 12, 2013, in New York City. (Andrew Burton/Getty Images)

The rationale was employed as the numbers of stops skyrocketed during the 12 years of Michael Bloomberg’s mayoralty. Such stops, endorsed and aggressively enforced by then Police Commissioner Raymond Kelly, rose from roughly 100,000 in 2002 to nearly 700,000 in 2011. The rationale was critiqued, by the New York Civil Liberties Union among others, but Bloomberg and Kelly pushed back, armed with year upon year of falling murder totals and other broad reductions in serious crime.

Ultimately, a federal judge, Shira Scheindlin, found the NYPD’s enforcement of stop-and-frisk racially unfair and unconstitutional. A new mayor, Bill de Blasio, and the judge’s orders for reform, prompted a radical scaling back of stop-and-frisk. Critics predicted a disastrous return to, depending on one’s age and experience, the 1970s or the 1990s.

The disaster never happened. Instead, what many scholars and police officials thought nearly unthinkable — further reductions in crime after two decades of plummeting numbers — did.

Holding murders under 300 was just the headline of 2017 statistics that saw considerable reductions in almost every category of major crime.

“Like many conservatives, I had grave concerns about curtailing the New York City police department’s controversial tactic of stopping and frisking potential suspects for weapons,” Kyle Smith wrote this month for the National Review.

“Restricting the tactic, I thought, would cause an uptick, maybe even a spike, in crime rates,” he added. “I and others argued that crime would rise. Instead, it fell. We were wrong.”

The achievement — curtailing both murders and stops — forced me to revisit my own decisions. I had the fun and privilege of serving as the metro editor of The New York Times for five years, but along with the occasional satisfactions came plenty of regrets. For me, none greater than my wish that I’d done a better job directing coverage of stop-and-frisk. My years as metro editor, 2006 to 2011, corresponded directly with the surge in stop-and-frisk.

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Let me be clear. The New York Times was blessed with the city’s elite law enforcement reporters, and they did lots of fine and enterprising work.

Al Baker and Ray Rivera, for instance, did a breathtaking report on a handful of blocks in one section of Brooklyn where over four years police had conducted 52,000 stops. Numerically, it amounted to one stop a year for every one of the 14,000 people living on the four blocks looked at. In the more than 50,000 stops from 2006 to 2010, the police recovered 25 guns.

That said, I still wish we’d had the series of stop-and-frisk stories Graham Rayman, then of the Village Voice, produced. An officer in a Brooklyn precinct had recorded his commanders as they sent their men and women into the streets to conduct random stops. The reporting, among other things, brought to light the potential that quotas had been set for officers.

I sent an email Tuesday morning to Kelly, the former commissioner, to see if he had thoughts looking back. I also emailed an invitation to the spokesperson for current Police Commissioner James O’Neill to talk about his department’s dual accomplishments.

“No one could possibly believe there could be 685,000 legitimate stops in a year,” the spokesperson, Stephen Davis, said. “We just focused more on learning how crime works. There are a small number of people responsible for a disproportionate amount of crime.”

O’Neill has taken some heat from the monitor charged with overseeing the department’s reform of stop-and-frisk. A report from the monitor late in 2017 said there was credible reason to believe a large number of police stops were not being counted. Still, the true total could be twice the roughly 10,000 claimed and remain a small fraction of the nearly 700,000 recorded in 2011.

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Regrets have an upside. They can provoke personal reform. And so when reporters for ProPublica and the Florida Times-Union set out to report on the enforcement of pedestrian tickets by the Jacksonville Sheriff’s Office, we were sure to ask some hard questions. The sheriff’s office has said they viewed pedestrian violations as probable cause to stop and question suspicious people. It was a sensible crime-fighting tactic.

We asked what might form the basis for considering someone suspicious, but the office was not able to say much beyond it could be “tips” about possible drug dealing or the like. We asked about how well the pedestrian tickets were tracked — who was receiving them and where. The office said pedestrian stops were captured incidentally with call logs and other reports, but were not specifically tracked. Officials said it would be “too burdensome” to capture the full scope of every pedestrian encounter and associated demographics.

The reporting, which showed pedestrian tickets were issued disproportionately to blacks in Jacksonville and that hundreds of tickets had been issued in error in recent years, has prompted several local legislators to call for reforms to the state pedestrian statutes and the issuing of tickets by the Jacksonville Sheriff’s Office.