Catholics are not to believe that capital punishment is intrinsically evil. It cannot be equated with abortion and euthanasia by one who submits to the authority of the Church. It is part of the traditional teaching of the Church that this severest of penalties is only to be used when certain conditions are fulfilled; one has to have the authority to execute this punishment. Punishment has four ends - retribution, deterrence, rehabilitation, and the peace of society.

"To judge justly, one must
1 have the right intention
2 have authority over the one judged
3 know the truth." - St Thomas Aquinas