The death penalty is supposed to be for the worst of the worst. The system of capital punishment in the United States has always assumed it was so, from its beginnings. Not all crimes may be punished with death, and not all trials for death-eligible crimes result in a death sentence. Therefore, the law must be set up to make rational distinctions, in order to guide prosecutors and juries to winnow out “the worst of the worst” as the recipients of the death penalty.

But as capital defenders have been saying for many years, the system doesn’t do that. Those condemned to die are not those who committed the worst crimes, but rather those with the worst luck, or the worst lawyers. And now there more is proof of that, this time in Connecticut. A new study by Stanford law professor John Donohue analyzed all murder cases in that state over a 34-year period and found that there is no rational distinction between inmates on death row and the equally violent offenders who were not sentenced to death. As Lincoln Caplan at the New York Times editorialized this weekend, the study shows that the process for determining who lives and who dies in Connecticut, like those in other death-penalty states, is “utterly arbitrary and discriminatory.”

The Donohue study affirms the notion that “luck of the draw” has more to do with who gets sentenced to death than a rational system of fair laws. Geography plays a big role: commit a murder in Waterbury, Connecticut and you are seven times more likely to go to death row than if you committed the same crime in Windham. And, shamefully, race plays a bigger role. The race of the victim and the race of the defendant are all too often the most reliable predictors of who gets a death sentence.

Forty years ago the U.S. Supreme Court temporarily suspended the imposition of capital punishment because the laws at the time failed to distinguish between “the worst of the worst” and those convicted people who should get a lesser sentence. The Court said that being condemned to death under those laws was so random it was like being “struck by lightning.” Statutes approved in 1976 were supposed to fix that. But a major review of the American system of capital punishment in 2011 found across the country just what Professor Donahue and his students did in Connecticut: the death penalty is still a matter of bad luck, bad lawyers (on both sides), race and geography.

The law cannot accept a system this chancy. Nor is the answer to try to make it uniform by executing all murderers – the Supreme Court has already said that’s unconstitutional, and even the most determined fan of the death penalty would likely not approve of executing the mentally ill, the very young, or those who made only one terrible error and are deeply remorseful. There is only one “fix” for the arbitrariness of the death penalty, the same one the Times calls for: end it now.

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