Blacks, which here means non-Hispanic blacks, were 12.5% of the U.S. population, and non-Hispanic whites were 60.4%. It thus appears from this data that the black per capita violent crime rate is roughly 2.3 to 2.8 times the rate for the country as a whole, while the white per capita violent crime rate is roughly 0.7 to 0.9 times the rate for the country as a whole.
Note: keep in mind he's extrapolating a certain part of the U.S, New York, to the rest of America's national crime statistics
It is...? Well, I can't be too surprised given the past history, post-Civil War, something something convict lease labor and reconstruction backsliding of Black people's human rights...