I have mixed thoughts about the death penalty. On one hand, giving the State power of life and death over its citizens is not good in my book, on the other hand we should understand that it already has it, whether we like it or not. If the state wants you dead, you're either dead or, if you're not, you're the Hulk.
There's a number of arguments against capital punishment that I believe are not exactly in touch with reality. For instance, the classical one is that it's no deterrent. Well, it happens nothing else is a deterrent, either. Jail is not, or we wouldn't have any need for them. Fines surely are no deterrent, more like a source of income in recent times. But sure as hell, prison doesn't seem to deter criminals much.
The true deterrent is - or should be - the certainty of punishment being carried out. The most hideous punishment isn't very effective if everybody knows there's no darn way they can be caught.
Then there's the little problem that perpetrators come in many categories, most of which are hardly deterred at all. The most easily deterred one is the most harmless - the ordinary guy who is driven to commit a crime out of need or desperation. The really desperate ones are not deterred at all because anything may be seen as a better outcome than their current situation.
Those who belong to organized crime have absolutely no fear of the legal system because more often than not, the underground society they live in has rules and punishments far harsher than anything we may come up with and, unlike us, their system guarantees punishment WILL be carried out. Ask anyone who ever had to deal with the mob.
What of the corporate weasel who embarks in illegal ventures? He's not very scared of the law either: he's got the money and the lawyers to buy his way out or to stall trials to kingdom come.
Then there are the sociopaths. They live in a different world. They do what they do because that's the way they're made. You could threaten them with anything from impalement to being buried from the neck down next to an anthill, and it would make absolutely no difference. Prison does not scare them. Ol'sparky does not scare them.
So, it's not about punishment di per se, but the ability of the police and the judicial system to effectively investigate and prosecute crimes, something that we unfortunately lack.
The other argument against death penalty is that it's not reversible. OK, but what about 40 years in jail? Happened to some guy just because of a mistake. Yes, he was freed but his life is gone. His family is gone. Might as well be dead, because sure as hell he's not going to get another take at life, and will be living the rest of it in bitter resentment. Mind you, even a short time in prison is going to pretty much destroy your life even if you're later recognized as innocent: your job will be gone and you'll be surrounded by suspect as long as you exist. By the time the system has "corrected" its mistake, your existance will be effectively over.
Some people still believe that the goal of imprisonment should be "redemption" of the subjects. This is wishful thinking. Sending a petty criminal to prison will result in a more hardened criminal upon release. And once they are released, what happens? Society does not easily reintegrates ex-cons. For most jobs nowadays you must have a clean criminal record, or you will not be good even for flipping burgers. It's an understandable policy on the part of employers because you can't take risks with employees anymore, but it also means that ex-cons will more often than not return to crime in a very short time.
And again, when you're dealing with sociopaths, there is pretty much nothing to do. As I said, I have mixed thoughts about the topic but it's because the whole system needs re-thinking, not just the punishment phase that should be the end of the process.
