Philippine legislators recently abolished capital punishment for a wide variety of crimes while the states of Oklahoma and South Carolina broadened their range of capital offenses. Canadians have been dead-set against the death penalty for decades - this might explain why they call their soldiers "peacekeepers."
Threat of the death penalty has not been much of a deterrent to say, murder. The concept has introduced gradations of murder into one legal system. First degree, second degree, manslaughter, criminal negligence causing death - capital or non-capital.
Lawyers for even self-confessed killers work very hard to have their clients convicted of lesser charges, a life sentence being seen as a comparative break in some cases. The clients were variously drunk, abused as children, walked in their sleep, juggled multiple personalities, were coerced into confession by police, or-that old chestnut-they didn't know the gun was loaded. Maybe so, but the victim is still dead.
In the western world, remorse works very well. A couple of generations have been taught that to say, "I'm sorry" will get them off the hook for just about anything. Political correctness is an outgrowth of this. Whatever our actions, whatever our true feelings, if we express them "nice," not foul, even if our tongues end up so out of synch with our motives and opinions we risk lockjaw, people approve. These days, "calling a spade a spade" is confined to poker or bridge games.
Of course there's always the possibility an accused has been wrongfully or erroneously convicted. Indeed, this happens. Juries are no more infallible than eyewitnesses. Unfortunately, the buck has to stop somewhere or it has no value. Its value today in capital cases is about on a par with an empty shell casing lying in a Baghdad gutter, primarily because of over-adjudication. There always seems to be one more appeal court, one more opportunity for legalistic hair-splitting.
In reality, capital punishment should be a non-issue as long as world societies indulge in overt political and sectarian violence, not to mention economic genocide. It is utmost hypocrisy to claim to be righteously civilized in the treatment of murderers while displaying on the world stage a savagery hardly seen in the wildest jungle.
Of course, people should not be permitted to run around killing anyone who displeases them. Vigilantes are frowned upon. Anarchists are loathed. No-one wants to spend their life looking over their shoulder in case some wacko is sneaking up behind them with a meat cleaver. We'd all feel a bit more comfortable if we knew that a disgruntled student isn't going to walk an automatic weapon into our children's schools, similarly an enraged employee into our workplace.
That said, perhaps the death penalty, not as a threat but as a certainty, may have some validity. However, so does life in prison without parole. Unfortunately, neither can occur until after the fact. Someone has to die.
The pros and cons of capital punishment are numerous and at the same time pointless. They have yet to provide a flashpoint for a light on the more fundamental issue of our underlying hypocrisy and our denial of its existence. We are what we are, and a coat of many colors cannot always cloak the aggression beneath it.