Surging violence in the country's third-largest city is fueling a rise in the U.S. murder rate this year, even as the nation's overall crime rate remains at "historic lows," according to a report Monday by the Brennan Center for Justice, a nonpartisan law and policy institute at the New York University School of Law.

The results, the analysis said, again refute false claims that crime is "out of control" – a phrase used regularly by Republican presidential nominee Donald Trump, though he was not singled out by name in the report.

"You'll hear Trump mention on the trail Baltimore, Milwaukee and Chicago – of those, Chicago is the only one projected to see violence increase this year," says Ames Grawert, an author the analysis and counsel at the Brennan Center.

He adds: "Chicago is the big story in this report."

Crime has fallen dramatically in the nation's 30 largest cities since 1990. Courtesy the Brennan Center

While the country's murder rate is projected to climb by 13.1 percent in 2016, nearly half that increase is being driven by Chicago. The city had recorded 528 homicides this year as of Monday morning, according to the Chicago Tribune – a tally that includes murder, but also justifiable killings like those committed in self-defense. The count has already surpassed the 491 homicides recorded through all of last year.

Chicago Police Superintendent Eddie Johnson has attributed the surge to gangs and street-crews – relatively small groups, he's said, that have had a disproportionate impact on violent crime. He's also pointed to broader issues, too.

"It's not a police issue, it's a society issue," Johnson told reporters on Sept. 6, just after Labor Day weekend, during which 13 people were fatally shot. "Impoverished neighborhoods, people without hope do these kinds of things… You show me a man that doesn't have hope, I'll show you one that's willing to pick up a gun and do anything with it."

The spike in murders in Chicago, third from left, dwarfs any increases in other large U.S. cities. Courtesy the Brennan Center

The Brennan Center's report found some correlation between higher homicide rates and entrenched poverty. Cities that had a 10-year trend of greater than average poverty and unemployment also experienced rising violence in the past two years, among them Chicago, Baltimore and the District of Columbia.

Although the nation's murder rate has soared by nearly a third since 2014, roughly half of that increase was driven by Chicago, Baltimore and Houston alone. And after Baltimore and the nation's capital each experienced spikes in murders last year, the two cities are on track to record sharp drops in murders by the end of this year.

Why Chicago remains in the grip of rising violence, there are a few potential factors: The Chicago Police Department has lost nearly 300 detectives since 2008 – roughly a quarter of all the detectives on the force – and the department's clearance rate for solving murders has sunk to one of the lowest in the nation. The state also abruptly cut funding for anti-violence programs in the city, a decision that correlates with a sudden spike in street violence.

The murder rate in the country's 30 largest cities has risen since 2014, but it's still far below the murder rate recorded in 1991. Courtesy the Brennan Center

Outside Chicago, by contrast, the picture was largely positive: Using mid-year crime data to project results through the end of 2016, the report found "reports of a national crime wave were premature and unfounded," adding that "'the average person in a large urban area is safer walking on the street today than he or she would have been at almost any time in the past 30 years,'" a reference to a similar Brennan Center report last year.