Can you share a link to Sowell’s research on driving while black and the differences between immigrants and those who were/weren’t descendants of slaves? All I could find was this, which ironically is mostly a bunch of anecdotes and does not mention anything about immigrants.
https://www.deseret.com/2007/11/1/20050686/thomas-sowell-little-evidence-to-support-the-dangers-of-driving-while-black
Looks like you may be confused with his research around economic success