The FBI reported Monday that crime levels rose once again in 2016. This marks the second consecutive year rates have risen, following nearly two decades of steady declines. There were 1.2 million violent crimes reported in 2016, up 4.1% from 2015. Rising crime in just a few major cities largely drove the spike in violence nationwide.

24/7 Wall St. reviewed violent crime rates in major U.S. cities from the FBI’s 2016 Uniform Crime Report. Violent crime includes all offenses involving force or threat of force and is broken into four categories: murder and nonnegligent manslaughter, rape, robbery, and aggravated assault. For every 100,000 U.S. residents, 386 violent crimes were committed in 2016.

1. Detroit, Michigan
> Violent crime rate: 2,047 per 100,000
> 2016 murders: 303
> Poverty rate: 40.3%
> Unemployment rate: 10.9%

Detroit, one of the several major metropolitan areas that are largely responsible for the increase in violent crime nationwide last year, surpassed St. Louis as the most dangerous city in 2016. The number of violent crimes rose 16.3% from 2015 to 2016, far more than the 4.1% national increase and one of the sharpest spikes of any U.S. city. The increase was largely due to a rise in the number of aggravated assaults, which increased by 30.6% year-over-year. In total, there were 2,047 violent crimes per 100,000 Detroit residents in 2016, by far the most of any city in the country and more than five times the national rate of 386 incidents per 100,000 residents.

One reason behind the violence in these cities — which at a rate of well over 1,000 cases per 100,000 people makes them among the most dangerous in the world — is weak police-community relationships.

In an interview with 24/7 Wall St., John Roman, a senior fellow with the non-partisan research organization NORC at the University of Chicago, said, β€œ a community that has demonstrated in the streets, that doesn’t trust the police the way it used to” — places like Chicago, Baltimore, and San Bernardino — β€œ… people won’t come forward as witnesses, they won’t talk to the police about why the violence is occurring.” In such conditions, Roman explained, crime tends to escalate.

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