You may have seen this graphic floating around.
The way the ADL lies with this is, they count Nazi prison gang violence, and drug-related violence from meth gangs and other white nationalist-affiliated groups. If a white supremacist prisoner shanks a crip, or a BGF, or a UBN, or whatever, it's "extremist" related
but not the other way around. No other gang or drug-related violence is included. You're supposed to get this idea the white supremacist violence is prevailing and everywhere, when what they do include even after they cherry pick amounts to a handful of murders.
The actual truth is, you have to think for all of five seconds to come up with how murderers in the US vote. It's not even tough
It is what it is.