While your statistics may be accurate enough, your conclusion violates my personal knowledge of the sometimes rampant racism in our justice system. A civil libertarian attorney friend has discussed some of his challenges to arrests and convictions with me and noted that police from several (largely democrat working class) suburbs of Boston routinely "just went out and arrested the first black man they found" to address a reported crime. He has been working for decades to free some of these victims. The statistics do not always tell a reliable story.
New Bedford, Massachusetts