Law enforcement has a built in “feared for life” defense. Prosecutors have to dismantle that defense in order to convict a police officer for killing an unarmed suspect.
The fact that a suspect is unarmed does not make the case easier.
It makes it harder.
All the defense has to point out is the possibility of danger. The slightest movement by the suspect will be portrayed as a life threatening gesture toward the accused. The defense will instruct the jury to put themselves in the police officer’s position. After the jury imagines the danger they have no reason to doubt the officer feared for their life.
The prosecution is burdened with refuting the fear factor to prevent the jury’s leap of faith. That means the prosecution has to convince the jury that a police officer’s fear wasn’t warranted.
Sometimes the prosecution proves there was no immediate threat to the officer right before the shooting, but the jury is still more sympathetic to the officer because the jury normally judges the action of a lone officer without any reference of comparison to the actions of other officers on the scene.
What separated the Terrence Crutcher police shooting from other high profile cases involving White cops and unarmed Black males was there was a total of four officers on the scene.