You must be living under a rock to not have read one of the bazillion of stories about policing and racism that have come up since last fall, but for a great overview of the subject I highly recommend The New Jim Crow: Mass Incarceration in the Age of Colorblindness [1]
[1] www.amazon.com/New-Jim-Crow-Incarceration-Colorblindness/dp/1595586431/