It does exactly what it says on the tin folks. Personally I believe that criminals get a relatively easy deal from courts, certainly in Britain; we have a system in which rape is almost never proven, petty crime is treated as a acceptable part of modern life and murderers can serve as little as a few years for taking the life of another human being. I believe that prison sentences should be longer, that prison regimes should be far harsher, with prisoners used as labour forces without pay and that Corporal Punishment should be reinstituted for offences which may not necessarily necessitate a prison sentence, but which are crimes or relative significance, i.e. theft, criminal damage, petty 'hooliganism' etc. However, I cannot support the death penalty as I believe that to employ the greatest of all punishments one must have a perfect judicial system.
We all know that there is no perfect police force, no perfect judge and no perfect jury. We also know that there are police officers who are not above planting evidence in order to secure what they consider to be the right 'result'. What this means is that the execution of a human being could take place because one police officer decides, for whatever reason, that a person is guilty and that they will ensure their conviction; thus a person can be killed based upon the subjective decision of another person. This is simply state-legislated murder.
Now consider the nature of the Western judicial model: We have an adversarial system, and thus it is essentially a competition between opposing lawyers. Anybody who has any experience of any form with the judiciary knows that it is very often like watching a ball game and there are few lawyers who are above bending the rules to guarantee the 'result'. Once again, we have a life in jeopardy thanks to the subjective whim of another person. Now consider juries: Twelve people, essentially pressed into service, often not paying attention and always prone to the same subjective and irrational responses which make a person human. One can call upon a single juror, twelve or twelve million, one still cannot guarantee the right result and therein lies the single and greatest flaw with Capital Punishment: It is irreversible. If the jury makes a mistake, or if the police do so, or the judge, or the pathologists, or the psychologists or the lawyers a person will be dead and there will be no way to reverse that. One crime will thus become two crimes and what purpose will that solve? Will it bring the first victim back to life? Will it ease the suffering of the living? Will it get a criminal off the streets? No. All it will do is sate the bloodlust of a society more interested in having it's fear assuaged, rather than attending to the simple issue of true justice.