An unknown statistic
http://www.vox.com/2014/8/21/6053811/white-on-white-murder
Back in 2011, the most recent year for which data is available, a staggering 83 percent of white murder victims were killed by fellow Caucasians.
This is not to say that white people are inherently prone to violence. Most whites, obviously, manage to get through life without murdering anyone. And there are many countries full of white people — Norway, Iceland, France, Denmark, New Zealand, and the United Kingdom — where white people murder each other at a much lower rate than you see here in the United States. On the other hand, although people often see criminal behavior as a symptom of poverty, the quantity of murder committed by white people specifically in the United States casts some doubt on this. Per capita GDP is considerably higher here than in France — and the white population in America is considerably richer than the national average — and yet we have more white murderers.