A July 26 Crime Prevention Research Center study found murders clustered in few U.S. counties. Thirty-one counties with 20 percent of the population had 41 percent of murders, 63 counties with 30 percent of people had 54 percent, and 5 percent of counties with 46 percent of residents had 71 percent of killings, nearly the same as in 2010. Counties with zero murders (53 percent) plus those with one (16 percent) produced just 3 percent of the total.

The same 63 counties had 57 percent of 2025 firearm murders versus 53 percent of all murders, and the 31 had 43 percent of gun murders; 78 percent of counties had zero or one. Biden won all but one of those 31 counties in 2020 and Harris won 25 in 2024, and the deaths occur mainly in large cities with Democratic mayors and councils.