Chad,
As I already mentioned (and is obvious anyway), the analogy wasn't equating negligence with homicide. It was illustrating an obvious example of contracts involving illegal activity being automatically null and void, and unenforceable in a court of law. I used murder, because it is so obvious to anybody why such a contract would be unenforceable. It helps people understand the concept. Then they can apply that same concept to less obvious/extreme circumstances, such as criminal negligence. It is clear to anyone, including yourself, that I am not saying that criminal negligence is the equivalent of murder, or carries the same punishment, etc. It is clear to anyone, including yourself, that I am simply saying that contracts apparently allowing illegal activity to take place are unenforceable. This applies to all illegal activity, murder, criminal negligence, jay-walking, etc. I simply do not have the authority to give someone else leave to engage in criminal activity of any kind - negligence or murder.
The purpose of analogies, Chad, is to help people understand a concept. If the analogues are exactly the same in every way, the analogy will be exactly as difficult to understand as the original example. Any normal person would read the murder thing and say, "Oh, yeah. Of course. It makes perfect sense that that would not fly in a court of law, for obvious reasons." It would then be easy for them to take the concept that they now have a clear understanding of, and apply it to the original example of negligence.