Did you hear that Connecticut abolished the death penalty? The state's practically next door, but somehow I missed this news when it happened in April, and just found it now. What's interesting is how it's part of a trend: Connecticut is the 17th state to abolish capital punishment (along with the District of Columbia, too), and the fifth in just five years.
When it comes to the death penalty, I believe the trends show: 1) the gradual abolishment of capital punishment in the world, 2) a glimpse - probably in our lifetimes - of a world in which the concept itself will feel outdated and barbaric, and 3) that this is part of a larger trend of decreasing violence. Capital punishment, even when carried out by a legitimate state with the support of its citizens, is still violence of a type. And as Gandhi taught, violence - though it can accomplish short-term goals - inevitably sows long-term problems (usually more violence.)
The decline of the death penalty in the U.S. can be tracked not just by the number of states endorsing it, but by two other trends. This chart shows one:
This is from Steven Pinker's Better Angels of Our Nature, and shows the rate of executions declining dramatically. That's right, even in the states that still have it on the books, it's mostly used less frequently.
In addition, Pinker brings up a good reason to abolish it: because it's a slippery slope. With execution on the books it's simply too easy to put innocent people to death. Did you know that during the last years of the reign of Henry VIII, there were over 10 executions in London per week? By 1822 England had 222 capital offenses on the books, including cutting down a tree. But by 1861 this had been reduced to four. The Wikipedia page on capital punishment in the U.S. has an interesting chart showing when the last execution was for each crime other than homicide. The last execution for witchcraft, for example, was in 1779, and the last for burglary was in 1941.
In fact, it's estimated that in the past 2,000 years, 19 million people were executed worldwide for trivial offenses. I had this same thought while reading Game of Thrones recently, as the capricious king in the book executes practically everyone who so much as glances at him funny. We take for granted the simple concept today - even if we support capital punishment - that the death penalty should be used only for dire offences, and only after a lengthy evaluation of guilt. Soon, there will be no offences left that we deem worth it.