I don't believe that making more laws will create that much change. If someone wants to get a gun and go shoot some people do you think they will mind breaking some laws to obtain the gun? No. It might deter some if they can't readily find a gun but its just like drugs. There are all sorts of laws to stop people from buying and using drugs yet it still happens.
I think we need to determine what is the underlying reason as to why violence is so prevalent in our society. I don't know what it is but something is wrong when so many people have such a lack of respect for others and life.