Chicago has become one of the country’s most violent major cities, while New York is now one of the safest. But if not for one factor — vastly different levels of gun violence — the murder rate of the two metropolises would be nearly the same.

In 2015, the most recent year for which data is available for both cities, the fatal shooting rate in Chicago was five times as high as it was in New York: 15.6 per 100,000 residents compared to 2.8 per 100,000. The difference between the rate for other types of homicide in the two cities is less than 1 percentage point.

The prevalence of fatal shootings in Chicago as compared to New York and other major cities is one of the starkest findings of a new report due to be released later this month by the University of Chicago Crime Lab, an academic research center that aims to help cities find ways to control violence.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

The report follows the deadliest year in Chicago since the early 1990s. The city recorded 762 homicides in 2016, according to the report, which was shared with The Trace in draft form — about 58 percent more than in the previous year. But homicides were not the only category of crime to rise: other gun offenses, including nonfatal shootings and robberies, soared.

“This suggests that what happened in Chicago in 2016 was less about an overall increase in the prevalence of antisocial or criminal behavior, but more about a focused increase in gun violence,” the report says.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

The violence has drawn national attention. On Monday, President-elect Donald Trump weighed in, tweeting that the city’s murder rate is “record setting” and suggesting that Mayor Rahm Emanuel should seek federal help if he “can’t do it” himself.

In fact, the report notes, though exceptionally violent, Chicago’s bloody year did not set a record for the number of people who were killed. The city’s murder rate spiked last year, but Chicago’s homicide rate was consistently higher in the early 1990s, the peak of the crack cocaine epidemic.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

As recently as December 2015, there was little indication that gun crime and homicide were about to skyrocket. The report describes Chicago’s crime increase as “sudden and sustained,” as illustrated in the chart below.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

Though it has received the most national attention, Chicago isn’t the only city that recorded a surge in killings last year. Nor it is the city with the highest per capita homicide rate. But among America’s largest cities — which also include Houston, Los Angeles, New York, and Philadelphia — Chicago experienced the largest jump in homicide rates in the last 25 years.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

As with previous years, most homicide victims in Chicago in 2016 were African-American men, killed in public places. More than 90 percent of homicides involved guns. Killings most often occurred as the result of an altercation. Most suspects had extensive arrest records.

The report did note one important change over previous years: police are recovering more powerful weapons from crime scenes. In 2016, police seized more 9mm and 40-caliber firearms than at any point in the last 15 years. This trend is not contained to Chicago. As The Trace has reported, police around the country are recovering higher caliber weapons, a shift medical experts warn could lead to increased lethality rates for shooting victims.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

The largest homicide increases took place in five of the city’s poorest neighborhoods, with more than 37 percent of their residents living below the poverty level compared to 23 percent for the city overall. Though only 8.1 percent of the city’s residents live in those five neighborhoods, they accounted for 32 percent of the city’s homicides in 2016.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

The draft report found few specific reasons for the crime spike. While extended periods of warm weather have been shown to lead to more crime, the authors noted that monthly temperatures were consistent with historical averages in 2016. Chicago’s spending on city services and public schools also held steady, although a state budget impasse disrupted funding for some community organizations. Though police made fewer arrests overall in 2016, they made about the same number as in previous years for violent crimes like shootings and homicides.

The report noted that arrests did not keep pace with the increase in violent crime. In 2015, police made an arrest in about 60 percent of homicide cases, whereas in 2016, they cleared roughly 40 percent.

“This decrease in the clearance rate is unlikely to have been what caused the surge in gun violence initially, but it may have accelerated this phenomenon — such as by fueling a cycle of retaliatory violence,” the report says.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

Police made fewer investigatory street stops than in years past. The Crime Lab report notes that police in New York City also made fewer street stops last year, a change did not lead to more crime there.

Credit: The University of Chicago Crime Lab
Credit: The University of Chicago Crime Lab

The draft concluded that the lack of answers about why crime spiked should not paralyze the city in its response to the crisis.

“The key lesson from the available data is that the problem to be addressed is not a widespread change in anti-social or criminal behavior in general, but rather a narrower one of gun crimes committed in public places, frequently by young people in our city’s most distressed neighborhoods.”