Investigations of Police Shootings

To have the U.S. Government to start an Agency to Investigate Police Shootings that end in Death in the United States of America, but have the investigators from other regions of the U.S. For example if the Shooting happens in the South region of the U.S... The Investigators come from the North, if shooting happens in the West coast region the Investigators comes from the East coast, and to have their Grand Jury Hearing done by a Special Prosecutor from another area as well and have Trials held in another state not the state where the incident happen.