Take it from Illinois, the death penalty is a moral embarrassment.

For decades, Illinois did its best to fashion a system for imposing the death penalty that would not ensnare innocent people. But, as one exoneration for a wrongful conviction was followed by another, our state came to realization that there was — and never could be — a fully fail-safe system.

That alone stands as a powerful argument in support of Pope Francis’ call on Thursday for the abolishment of the death penalty worldwide.

We also would urge every state in the Union that still employs the death penalty to take to heart the pope’s simple moral argument: the state-sanctioned killing of individuals is “an attack on the inviolability and dignity of the person.” It deprives the guilty — even the most awful offender — of “the possibility of redemption.”

To this we would add one further argument: Not one good study has ever shown that the death penalty deters violent crime. When a society resorts to brutal violence to solve the problem of brutal violence, it is turning its back on reason.

Unlike many other states, Illinois has long supported a network of public defenders. These public defenders do a markedly better job of defending indigent clients than do many court-appointed lawyers in other states, who typically are paid a pittance. Moreover, Illinois instituted a string of reforms over the years to ensure that defendants in death penalty cases received fair trials.

Yet, for all of that, the system never worked flawlessly, and it had to work flawlessly.

EDITORIAL

Illinois has a more spirited and fair-minded appellate court review process than in some other states, which is how our state came to discover that a dismaying number of innocent people had been wrongfully sentenced to death.

Today, Illinois is among the 19 states that have abolished the death penalty. Four other states have moratoriums. Most predominantly Catholic nations also have done away with it.

Worldwide, more than 20,000 people are awaiting execution, according to Amnesty International. But over the millennia, people have come to realize that widely accepted but morally repugnant practices, such as torture and slavery, have no place in a just world.

Capital punishment should be added to that list of banished barbarisms.

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