Malice aforethought is kinda like premeditation but not truly the same. I'm not familiar enough with SC law to try to explain the difference.
Also, as SC appears to be a true grand jury case, I don't know that it is accurate that he has been charged with murder. It seems more likely that the prosecutor is asking for an indictment for murder.
I have a hard time seeing this as other than murder, but I agree it could result in a manslaughter conviction.
Me too. The one thing that seems clear from the video is that the officer knew the man was not in a position to harm him when he aimed and fired his weapon. The only thing that I guess would be open to argument is whether or not the officer intended to kill the man. I always have trouble when an application of definition depends on a person's thoughts or intentions. In all but the most extreme cases, you really can't be absolutely sure of a person's intentions.
I would have a hard time believing that the question of whether or not it constitutes murder if a police officer shoots and kills a fleeing, unarmed (and not apparently dangerous) suspect hasn't been well settled by precedent.