Cops are always hiding behind the same lame shield, "the officer fired in self defence", "the suspect appeared to have a weapon", "the officer fired when there was a credible threat to his life"...
It's all fucking bullshit. The officer fired because he was a big fucking pussy who was too afraid of black people to do his job, and instead killed an innocent he was supposed to protect.
In war you have rules of engagement, generally it tends to include something like "don't fire unless you're fired upon", as you don't want to accidentally start a war. That seems like a sensible code to me, and I think it's pretty crazy that we would say that to soldiers, but not police. A fighter pilot can track another aircraft, knowing full will that it is armed, and if they are not cleared to engage, they still manage to stand down every time. Perhaps police just need clearer rules. Don't fire unless fired upon, or else it's murder. That would be clear. Since apparently you can't take the racist out of the cop, then we can at least take the decision making out of his hands.
Firing because you see someone who might be armed... That's just deportable, it's criminally incompetent. I don't care if you're afraid for your life, if you were afraid for your life because you thought you saw a gun, quit the force. Today.