Troy Davis execution: Did the death penalty deliver justice?

For his supporters, the execution of Troy Davis marked a grave injustice and showed the death penalty at its worst. But others found their faith in the justice system reaffirmed by the fact that the Davis verdict stood after an abundance of case reviews.

A last-ditch appeal to the Supreme Court pushed back Troy Davis's execution by several hours, but in the end, Mr. Davis died by lethal injection Wednesday night in a prison in Jackson, Ga.

"I am innocent," were his last words to the family of Mark MacPhail. "I did not have a gun."

Mr. Davis was convicted of the 1989 murder of Mr. MacPhail, a Savannah, Ga,. police officer.

For thousands around the world, Mr. Davis's death marked a grave injustice, given vexing questions and new doubts about his guilt.

But while many saw the execution as symbolic of a fallible justice system, and an immoral punishment, others found their faith in the system reaffirmed by an abundance of court and executive reviews that, time after time, let the verdict against Davis stand.

The Davis case is but one in a long series of death penalty cases that push individual states to debate the morality, legality, and efficacy of the death penalty.

This week alone, the US Supreme Court ordered stays for two men in Texas scheduled to be executed, while a third, Lawrence Brewer, was executed Wednesday night for the dragging death of James Byrd near Jasper, Texas, in 1998. Alabama has an execution scheduled Thursday.

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Davis was convicted in 1991 for the shooting death of off-duty police officer MacPhail, who had come to the aid of a homeless man being beaten near a Savannah, Ga., Burger King. A jury of seven blacks and five whites found that Davis had shot a man earlier in the evening and used the same gun to fire into MacPhail's face and chest, killing the young father of two before he had a chance to draw his weapon.

The murder weapon was never found and defense lawyers cast doubt on a ballistics test that linked shell casings at the scene to casings found at another shooting for which Davis was convicted.

Since the verdict, seven of nine witnesses in the case changed or retracted their accounts, and new witnesses have pointed to the possibility that another man at the scene fired the weapon. But Federal District Court Judge William T. Moore said those new statements amounted to "smoke and mirrors" to obfuscate the original verdict.

On Tuesday, a Georgia clemency board, for the fourth time, declined Davis's request to commute the sentence to life in prison. The Georgia board has commuted three other death row sentences in the last decade.

President Obama, through his press secretary, said he had no jurisdiction to intervene in a state court matter, although experts say executive power under the Constitution includes the power to commute sentences.

One problem, legal analysts say, is courts are vested in jury verdicts, which can be fallible. Doubts alone are rarely enough to overturn a finding of guilt, but in cases like Davis's, where there is impassioned belief of innocence, it "raises doubts about whether the legal system can tolerate this potential error in allowing a person to be executed," says James Acker, a criminologist at State University New York in Albany.

But the Davis case also had powerful emotional impact that made him a cause célèbre among human rights activists working to end the US death penalty. A black man being executed for the murder of a white man in the Deep South raised longstanding and deep-seated concerns about racial inequities in the justice system.

Davis's execution stood in sharp contrast to the execution the same day in Texas of Mr. Brewer, a white man convicted and sentenced to death for a heinous hate crime against a black man.

"Can we have the death penalty and actually avoid the possibility of killing innocent people?" writes Rashad Robinson, executive director of the activist group Color of Change. "In a criminal justice system that routinely misidentifies black suspects and disproportionately punishes black people, black folks are more likely to be wrongfully executed."

Death penalty opponents often point to the fact that over 130 death row inmates have been released since the 1970s given new evidence, including DNA. But proponents of the death penalty use the same data to argue that those numbers validate what Supreme Court Chief Justice William Rehnquist once called executive branch "fail-safes," such as clemency boards, that prevent the execution of the innocent.

President Jimmy Carter said the Davis execution should result in the abolition of the death penalty in the US. "If one of our fellow citizens can be executed with so much doubt surrounding his guilt, then the death penalty system in our country is unjust and outdated," Carter told the AP.

Sixty-four percent of Americans support the death penalty to punish egregious murder, according to a 2010 Gallup survey.

Whether the Davis case has an impact on the use of the death penalty in the US in the future is an open question. Already, the number of executions in the US has been steadily dwindling over the past 15 years, even in Southern states where capital cases are most common.

Meeting with activists before his execution, Davis reportedly said, "You have a choice. You can either fold up your bags after tomorrow and go home, or you can stand and continue to fight."

Some still see the uproar over Davis's execution as "manufactured" emotion smartly packaged by activists and the media to build opposition to the death penalty.

"We have consistently won the case as it has been presented in court," said Spencer Lawton, the original prosecutor in the Davis capital murder case. "We have consistently lost the case as it has been presented in the public realm, on TV and elsewhere."