It is my firm belief that when society is trying to punish a person for committing a crime, death penalty cannot be an appropriate choice of punishment. There is one thing, I was told by my school law teacher that may sound very surprising to many people: when we sentence someone with any kind of punishment we are actually punishing not a person that committed the crime. Hard to believe, but it is true.
Most of criminals, after committing their crimes spend a lot of time thinking about what they have done and actually realize all impact of that action on their lives, on lives of other people or all society. A criminal who confessed is not the same criminal who just robbed, raped or killed.
As it is well known by most of lawyers, there are two main goals of legal responsibility: prevention of the crime and actual punishment. I want to stress on the fact that the first one is more important that the other one. Society is trying to reeducate a person who does not want to obey the rules, in order to prevent this criminal from committing the same crime in the future and to prevent all other from doing the same actions.
By simply killing a person we choose the easiest way of solving the problem, but not the best one. Instead of trying to change a criminal into a law binding citizen and convince him or her to follow the rules, we take away from this person his/her last chance to confess and change. Even if a person truly realized his or her mistakes and accepted them, by restoring capital punishment we forever deprive this person of chance to become different.
The main idea is that right to life is one of the fundamental rights of every person and no one can take it from anybody under any circumstances. The act of prohibiting death penalty in all of the countries can make a similar impact on the history of humanity as the Abolition of slavery in the USA in 1862 did.
Finally we have to remember that we are judging not a person, but a crime and remembering...