Watch and listen to the video.  Sammy was  not about to kill anybody.  He was standing at the door of the streetcar.  Nobody else was on it.  If the police had thought he might lunge out at them they could have stood 10 feet away.  There was time to talk to him.  Neither he nor the streetcar was going anywhere.  He was shot by a policeman whose fear overcame whatever brains he had.

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