I'm not so sure about that. An officer can shoot a fleeing suspect (even in the back) if he reasonably believes the suspect is a threat to the officer or others. If the suspect had the officer's taser, then the officer had an argument (and a pretty strong one at that) that the suspect was a threat to others. So, he put the taser near the victim to make it look like he still had it, thus justifying the shooting.
Remember, the officer murderer's attempted cover-up very nearly worked. The police department put out a statement after the shooting that essentially backed up the murderer, and, after the video came out, the mayor said that they would not have been able to "resolve" the situation without the video. Bullets in the back or not, without the video, the murderer would have gotten away with it.
Good points.
I know this is off topic some, but this whole idea that a taser is non-lethal force when the government uses it on you, but you are an immediate threat to do great bodily harm to the government agent or others around you if you take the taser from the government agent, is just weird. I guess part of it would be a fear the government agent could be based and his weapon taken, but still that does not get to a threat to others around when one is running away. Still it is an odd bit of logic that in the government’s hands a weapon is a non-lethal multiplier of force, but in a private citizen’s hands it make the person an imminent danger to others.