is capital punishment justifiable???

Capital punishment is known as the death penalty mainly for unpardonable crimes such as murder, trafficking and taking of drugs and kidnapping of others. i feel that capital punishment is justifiable as these are the crimes that destroy or violate human rights.
Others may disagree to my point about punishing murderers in such a brutal way. as they may argue that it is a violation of human rights of the murderer and that it cannot bring the dead back to life by taking the life of the murderer. If it is seen as a violation of human rights, then what gives the convict the authority to violate the victim's human rights? if so, then shouldn't judges be, too, given this same authority? Also, capital punishment acts as a deterrence to those who intend to violate the rights of fellow human beings. And once the criminal is executed and buried, there is no further maintenance cost to the state.
Again, these statements may cause a controversy among people. they may argue that we should be merciful and that convicts should be given a second chance. such a project can be seen from the yellow ribbon project whereby criminals are given opportunities to learn skills so that they can be accepted into the society once more. However, as the saying goes, "a leopard doesn't changes it spots". As statistics proves that 30% of prisoners are not first time offenders and they cannot change their behaviour. Hence, by keeping them or by trying to help them change for the better is merely a waste of the state's resources. the yellow ribbon project is only for thoses who have committed crimes that are not serious such as stealing and thus does not apply to those facing capital punishment.
Hence, my stand is that capital punishment is justified. Just do good and you wont have to face issues pertaining to these :)