And here's the thing.
When a black person kills another black person, he is arrested. He is tried. He is convicted. He goes to jail.
When a white cop kills an unarmed black person, the police cover it up, often lying to the public about what happened until a video pops up. Prosecutors decline to press charges, or even act like defense attorneys (as they did in the cases of Michael Brown and Tamir Rice). on the off chance they are convicted, they get minimal sentences like Jason van Dyke (only 7 years of which he served 3) or Kimberly Potter (only got two years, of which she served 16 months)