Why Comparing Crime Statistics May Not Pay

November 17, 2018 Updated: November 17, 2018

Overall crime in New York City continues to decline according to the latest figures released on Nov. 7, with Mayor Bill de Blasio describing the Big Apple as “the safest big city in the country.”

It’s a contrast to headlines over the pond in London, where government figures indicate a rise in serious violent crime, including a recent surge in knife offenses.

But the statistics often don’t reflect the experiences on the ground.

‘A Grain of Salt’

Monthly figures from the NYPD show an overall decline in “index crimes.” This covers murder, rape, robbery, felony assault, burglary, grand larceny, and car thefts.

“As we near the end of 2018, I am very optimistic about where we find ourselves,” said Police Commissioner James P. O’Neill at New York City’s monthly crime briefing on Nov. 7.

Recorded shooting incidents were down by 13 percent this October compared to last year.

While the numbers do show a drop in many offenses, Rafael Mangual, deputy director of legal policy at the Manhattan Institute, says it doesn’t paint a picture of what’s happening at a local level.

For example, according to NYPD figures, citywide shootings have gone down compared to last year. But the breakdown of data shows that 86 percent of all shootings happened in the Bronx and Brooklyn.

For those neighborhoods, shootings went up in Brooklyn North by 15 incidents, while in Brooklyn South and the Bronx they dipped slightly compared to last year.

“It highlights some of the problem areas you might not see by just looking at the city wide numbers,” he said.

He says to take average statistics with “a grain of salt.”

Numbers Fluctuate

Police figures are sometimes susceptible to change.

Earlier this year, figures suggested that London’s homicide rate beat New York’s in February and March for the first time in modern history. Both cities have similar populations of over 8.6 million.

Going by the latest numbers, this still holds true for February. But more recent police figures recorded on the Met’s crime dashboard, show London’s recorded homicide total dipped in March, making the rate lower than its American cousin.

A police spokesman explained in an email, “It might be the case that a death, which was originally thought to be a murder was found to be non-suspicious.”

In addition to this, the ways that crime data is collected differs, even within the same country.

“I tend to hesitate to draw a broad conclusion for city-to-city comparisons at the higher levels,” Mangual said.

Instead of just looking at the numbers, he says it’s important to contrast police practices in different regions.

He said that New York city is a “shining example” of successful police practices partly driven by the long-term effect of the “broken windows” policy. He hopes that the city continues to be vigilant to prevent violent crime.

Homicides in Numbers

(Source: London’s Metropolitan Police and NYPD, Oct. 2018)

New York – 20
London – 10

New York – 14
London – 18

New York – 21
London – 18

New York – 22
London – 16

New York – 34
London – 13

New York – 31
London – 8

New York – 24
London – 6

New York – 23
London – 11

New York – 27
London – 7

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