What kind of human being does such a thing?
Watch as an Indiana police officer, sworn to protect and serve, pushes a paraplegic man over, out of his wheelchair on the sidewalk, over a curb and onto a paved road surface. The man had accidentally run over the officer's foot as he was leaving, surely a crime worth punishment by being tipped over and possibly having one's skull split.
One of the other officers present then says "Now you're going to jail!" (The charges were eventually dropped.)
The incident happened in October, 2013, but the video was just released yesterday.
The officer? Oh, he wasn't fired. He's back on the force, on probation, probably out looking for 3 year olds on tricycles violating the vehicle code so he can "tip" them.
Here's a non-embeddable video with a news report of the incident which has more details.