The United States' murder rate has risen over the past two years, driven mostly by violence in a few large cities, a study released Tuesday said.
The report from the Brennan Center for Justice at New York University School of Law showed the national murder rate rose 10 percent in 2015 and an estimated 7.8 percent in 2016.
Baltimore, Chicago and Houston accounted for almost half of the increase in murders, the study said. In 2014-16, killings in Chicago accounted for 29 percent of the national murder rate spike, while killings in Baltimore and Houston each made up 10 percent of the rise.
The authors based the 2016 numbers on preliminary FBI data from the first half the year. They used this midyear data to predict what crime rates would look like for the second half of the year.
Even with the recent spike in murders, America's murder rate still remains near the bottom of a 25-year decrease, and the study authors note: "Today's inner cities' are safer than at almost any point in the past."
"In 2016, killings in Chicago accounted for nearly half (43.7 percent) of the increase," the authors write, referring to urban totals. "This is indicative of localized problems in some cities, but not evidence of a national crime."
Despite the increase in murders in several American cities, America's overall violent crime rate is about 49 percent lower than it was in 1991, and the violent crime rate in the nation's 30 largest cities has declined by about 63 percent during that same period.
"These spikes in urban violence are a serious cause for concern," the authors write. "But history shows these trends do not necessarily signal the start of a new nationwide crime wave, and even with these increases, crime and murder rates remain near historic lows."