I'd like to know why such laws are written in the first place. Why does it particularly matter if the murderer thought their individual blow(s) to their victim(s) would be "the" lethal blow or not? The fact is they intentionally KILLED somebody. I think if it is proven beyond a reasonable doubt that they murdered somebody, regardless of their motivation or feelings at the time of the killing, they should be executed. Doesn't matter if it's 50 victims or one. End of story.