IDK if that's the reason. I was asking if that was a possibility. If you mean disproportionately to whites, and you know this, it is 67% to 25%. Do you believe that has an impact? I believe you might have been leading up to the reason the number is 67%? According to one of my friends here it is because of Slavery.
If slavery is the cause then go back in time to when the slave trade was developing in American and involved black African nations dealing away their own people in the 1600s and before. As you know slavery didn't begin in America (Not the USA) during the 18th or 19th centuries. Unfortunately, you'd never know that by reading most history text books which focus on the cotton gin being the primary driver of the slave trade in the US.
This is that hard to piece together fellas. The US government failed to grant basic human rights to a portion of our population for a substantial period of our history. The effects are still being felt today.