The public revelation of Laquan McDonald’s shooting death at the hands of Chicago Police Officer Jason Van Dyke rocked Chicago and cost then-police Superintendent Garry McCarthy his job.

The late-2015 court-ordered release of video footage from a year earlier showing the white officer shooting the black teenager 16 times ignited protests over police treatment and calls for reform. Three years later, McCarthy, now running for mayor, is still defending his record from that era.

“As superintendent using the plan that we put together in Chicago, we were able to reduce crime by almost 40 percent over the almost five years that I was the superintendent,” McCarthy told a crowd during a recent City Club speech before trotting out several other statistics from his time on the job. “But the one that nobody seems to know is that there was almost a 70 percent reduction in police-related shootings under my tenure because of training, supervision and policy decisions. Almost 70 percent reduction in police shootings. But one shooting obviously blew up the world here.”

We didn’t know that for a fact, although we’d heard McCarthy make the claim before, so we decided to check it out.

Number crunching

As he criss-crosses the city campaigning for mayor, McCarthy is clearly trying to blunt criticism he oversaw a police department that treated minorities unfairly. His argument about police shootings has become one of his talking points on the stump to try to upend what he’s previously described as the “revisionist history” that evolved surrounding him, the McDonald case and his oversight of the department.

But McCarthy’s recent statement backing up that argument is less than clear. For one thing, he didn’t specify the time period he was comparing his record against. Was it the single year before he arrived at police headquarters in 2011 or several years prior? And was he only comparing those stats to the tally for 2015, his final year on the job, or more than that?

A spokesman for McCarthy didn’t help clear up that issue. He told us only that his candidate had drawn his figures from a statistical analysis conducted by the police department itself, but provided no details on how McCarthy did his math or even where to find that report.

So we turned to statistics reported by the Civilian Office of Police Accountability, which is a city agency that reviews allegations of misconduct against Chicago officers. Those reports list the number of notifications the agency has received from CPD of officers striking an individual after firing a gun.

No matter how we crunched those numbers, the results generally supported the first beat of McCarthy’s claim. While the decrease didn’t quite approach 70 percent, officer-related shootings did fall substantially during his time as the city’s top cop.

The number of police shootings that occurred during McCarthy’s final year on the job was 57 percent lower than it was in the 12 months before he took the post. When we broadened the range to compare his last two years with the two years preceding to his tenure, we saw a smaller but still significant decline of 38 percent.

That data has a few limitations. Officer suicides may be included in the tallies, for instance. And the sample size itself is so small that a slight uptick or downturn can cause the percentage change to fluctuate substantially. The figures are also reported on a quarterly basis. Since current Mayor Rahm Emanuel ousted McCarthy on Dec. 1, 2015, we turned to the Chicago Tribune, which assembled its own database of police shootings between 2010 through 2015, to find out how many shootings occurred at the end of the year after McCarthy’s departure.

It’s worth noting that when we compared the number of shootings in McCarthy’s last year with those in the 12 months prior to him taking the job using the more comprehensive Tribune data, we got slightly more muted results: a 51 percent decrease, compared to the 57 percent result we got with the COPA numbers.

‘Success has a thousand fathers’

The second beat of McCarthy’s claim — that the decrease can be chalked up to decisions made under his leadership — stands on shakier ground.

For one thing, much of the decline under McCarthy took place in his final year, between 2014 and 2015. Police shootings have continued to fall since McCarthy left, suggesting greater forces may have been at play than McCarthy’s leadership alone.

“There’s an old adage that success has a thousand fathers,” said Samuel Walker, a professor emeritus at the University of Nebraska at Omaha and an expert on police accountability. “Everybody’s going to want to chime in and make claims … something they did was responsible for this decline.”

But the myriad factors affecting officers — both within the department and on the streets — are “hugely complex,” Walker cautioned, making it practically impossible to single out any one among them.

Walker also pointed to the continued decline of violent crime in large cities in recent years, which can translate into fewer robberies and similar altercations that put officers in situations where they might be more likely to fire a weapon.

Data from the Federal Bureau of Investigation backs that up. Nationally, the reported number of fatal shootings by officers — “justifiable homicides,” in FBI parlance — has fallen fairly steadily since 2013.

Our ruling

McCarthy said, “there was almost a 70 percent reduction in police-related shootings under my tenure because of training, supervision and policy decisions.”

He’s correct that a significant decline did occur on his watch, according to city figures, although the decrease was a bit smaller than he claimed.

Experts, however, cast doubt on whether McCarthy could take credit for the decline, saying it’s virtually impossible to peg it to a single cause. And national crime data suggest Chicago’s drop in police shootings could be part of a larger downward trend.

HALF TRUE – The statement is partially accurate but leaves out important details or takes things out of context.

Click here for more on the six PolitiFact ratings and how we select facts to check.

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