Basically this is the timeless question of Nature vs. nurture. Through all the years this one has failed to garner a straight answer from me. There are elements of both, I believe, which make the case for innate actions which are built into the human being, and those actions which can be attributed to tradition, values, and morality.

I think every human being is capable of murder. Everyone. And anyone who says they aren't just has not been in a situation that made them capable. Humans lose control, and none of us are perfect.
If someone killed a loved one? If the circumstances were so that it was preventable?
We all know laws are man-made. So I believe that through the years people made that law because they have been in this predicament. And so they have figured it out on their own, and didn't need a law to tell them. I think they just wanted to save some lawyer bills for the rest of us? :thumbsup:
Taking ones life is serious, but you don't need the law to tell you that. The laws have been crafted through various needs demanded by society, and not all of them make sense to all people.
Now, if you asked people two questions.
a) Do you think you're capable of murder? - Lets assume the majority say no.
and then
b) If you knew someone killed your mother/father/sibling/child, do you think you are capable of murder? - I would trust most people would say yes.
Two wrongs don't make a right yes...but thinking as a human being...you ARE capable most times when thinking of a situation such as this one.

This is where the clusterfuck starts
You won't normally act upon it, but you consider it. Do you refrain because society tells you its bad? I say no. You refrain because to take a life is the worst crime one human can do to another. Life is a gift - if you think about how INSANE it is that people, the planet, or the universe is..the fact that we are all here...just living...? It's nuts, and each day is a gift. Cause none of us know whats going to happen. Bottom line for me is, you don't take the life because it's terrible. That's where the initial laws against it have come from. And I don't think you needed the law to tell you that.

That being said, there is a direct relation between societal norms and behaviour. Undeniable. I just think there are a few things you are born with the capability to do, but can rationally persuade yourself not to do.
And I don't think its the law. Cause if I went with the law all the time, I wouldn't smoke weed. And we all know that's not the case.