How does police and prosecutorial discretion allow for racial and ethnic discrimination in the criminal justice system?

. Department of Justice Investigation of the Ferguson Police Department,opens in a new window 2015, pp. 9-41, 62-67 and 69-102 (PDF formatopens in a new window) View:: How does police and prosecutorial discretion allow for racial and ethnic discrimination in the criminal justice system? Is allowing such discretion desirable, when used fairly? What are some ways of curbing or checking this discretion to make the system more fair? Do you think these things will be effective? Why or why not?