But that is what it MEANS, unfortunately. A higher incarceration rate does NOT prove a higher criminal rate. No reputable study shows a significantly higher rate of marijuana smoking by blacks than whites, and blacks make up only about 10% of the population ... yet they make up over half of all the folks incarcerated for marijuana possession! There are reasons why things happen in societies, and aggregate studies over millions of folks well illustrate those societal trends. Your presumption that higher incarceration rates means that more of "them" are committing crimes is exactly what we are discussing here. Given police methods and (perhaps unconscious) prejudice by prosecutors and juries, there ARE very valid reasons why so many young black men wind up in the criminal justice system ... and perhaps that is a symptom, not a cause.