Americans seem increasingly comfortable with the idea that government actors shouldn't be criminally punished. That's antithetical to the rule of law. Criminal law applies to everyone or it's not really "law." The Supreme Court did not help matters with its decision in Trump v. US.
They also made him sleep on the floor of a holding cell. With the bullet in his back. And no pain medication. They also failed to provide medical care after they shot him.
People need to go to prison for this.