In short, the system certainly does not work. In the above case, one could reasonably conclude that this individual should not have been put to death - even the prosecuting attorney seems to agree with this position. It is a very arguable point as to whether the system is working!
then work to change the system not try to get rid of the solution. like i said you complain about the penalty when the problem is a corrupt system. I know of 1 man that was robbing crack houses in Missouri and Kansas. The states did not want to prosecute him because he would make them look bad because he was putting crack houses out of business. The feds arrested him but couldnt try him for robbery as there is no crime of robbery in federal law. They charged him for interfering with interstate commerce because the electricity to the houses came from texas and the gas came from oklahoma. He got 2 life sentences. The people that were sent to prison because of a corrupt system is the problem. If they want you they can get you.