It may very well be Constitutionally legal to execute the innocent:
Twenty years ago, off-duty police officer Mark McPhail was shot and killed in a Savannah, Georgia parking lot. Based on information provided by Sylvester Coles, the police sought Troy Davis for the murder. He was found guilty and sentenced to death based on the testimony of eyewitnesses.
Since then, however, nearly all of those witnesses have recanted, claiming in affidavits that they were pressured by police to name Davis as the perpetrator. Meanwhile, additional evidence has been found indicating that Coles, the prosecution’s star witness against Davis, was the actual killer … neither the Georgia courts nor the Georgia Pardons and Parole Board has seen fit to stop Davis’s execution.
Last week, the Supreme Court offered Davis a ray of hope. In response to his petition for a writ of habeas corpus, the Justices ordered that a federal district court in Georgia “should receive testimony and make findings of fact as to whether evidence that could not have been obtained at the time of trial clearly establishes [Davis’s] innocence.”
The Court’s order in Davis was not unanimous, however. Justice Scalia, joined by Justice Thomas, dissented. Justice Scalia said that even if the district court were to find Davis to be innocent, there would still be nothing unlawful about executing him.
I’ve always been oddly attracted to the weird disconnect between our laws and common sense; the legal grey areas surrounding what should be stark black and white. This is no different.