PERHAPS IT IS because jurors have grown leery of a penalty from which there is no recourse. Perhaps it is because states have had more difficulty obtaining the drugs used to put inmates to death. Perhaps it is because of the continuing drop in the murder rate and the fact that four states in the past few years have decided to abolish capital punishment within their borders. Regardless of the reasons, there is cause to celebrate the drop in the number of executions in 2011, as well as the precipitous decline in the number of new defendants sentenced to death.

According to the Death Penalty Information Center, 43 inmates were executed last year — three fewer than during 2010 — and barely half of the 85 who were put to death in 2000.

Although Texas maintains the dubious distinction of leading the country in executions, even the Lone Star State seems to have less of an appetite for the ultimate retribution. Thirteen individuals were put to death in Texas this year, down from 17 in 2010. Closer to home, no inmates were executed in the District or Maryland in 2011; one inmate was put to death in Virginia — two fewer than the year before.

Most encouraging, juries and judges have been less willing to impose death sentences. In 2000, 224 inmates were so condemned. That number was less than half that in 2010, or 104. This year, only 78 inmates were sentenced to death.

Reasonable people can take exception to our view that capital punishment is unworthy of a civilized nation. There are crimes so heinous that even abolitionists like us are given pause.

But even if one accepts a philosophical divide that rational argument isn’t going to settle, the risk of executing an innocent person must weigh heavily in the debate. There can be no denying that the criminal justice system makes mistakes. Seventeen people sentenced to die in the United States have been exonerated by DNA evidence, after serving a combined 209 years in prison, according to the Innocence Project. Hundreds more subject to non-capital sentences have also been freed as a result of DNA testing. For many convicts proclaiming innocence, there isn’t and will never be DNA evidence to provide certainty.

Public safety and appropriate punishment for the worst crimes can be achieved through life sentences without the danger of taking an innocent life.