Especially when the individual in front of them refuses to obey their simple commands.
Crawford was given no commands, the cop just shot him on sight. Where Crawford's actions stupid, you bet, where they illegal, no.
Tamir Rice, a 12yo who had a toy bb gun pistol. The person who called 911, told the dispatcher both that the boy was most likely a juvenile, and the gun was likely fake. The cops pulled right up on him, damn near running him over, jumped out and shot him. If the cops are thinking about their safety, and they are trying to take someone they think has a pistol into custody, In a case like Rice's, they should have left about 50 yards between themselves and the person with a gun, had him put down the gun, and walk there way. Not pull right up on him and just start shooting.
You might think it's ok for cops to just shot people on site, I Don't. If either party had pointed their guns at the cops, it's a no brainer, the cops can shoot them, but neither did. In neither case did the police even attempt to get the person to put down the toy weapon. They shot first, then cleared themselves of any wrong doing latter.