The person in front would be justified to shoot when he did.
The second person should be charged with murder/attempted murder.
Seems pretty obvious.
It seems pretty obvious that only one person fired all three shots.
@CountValentine, put yourself in the shoes of the guy with the red sweater. Would you indeed fire one shot and then put away your weapon? Knowing that this scum just tried to run over a person, got out of his car and stabbed him, and then three others, and lunged at a person who is trying to stop him with a drawn hand gun. Just one shot, and put away your weapon once he's on the ground regardless of whether you notice him moving or not once he's down? Just like that, with a clear cold and controlled manner, just like captain Sully was when landing on the Hudson river?