From Wiki:
Premeditated murder is the crime of wrongfully and intentionally causing the death of another human being (also known as murder) after rationally considering the timing or method of doing so, in order to either increase the likelihood of success, or to evade detection or apprehension.
If the charge were premeditated murder...and you and I were on the jury...It would not be unanimous.
From what I have seen, it is without excuse, not a good decision...tragic...But not premeditated murder, maybe murder in the second degree...
Slager definitely wanted to put the guy down while he was running away. You or I would fry for this!