The defendants were convicted, given a burden of guilt, and then that burden was lifted when they were acquitted at a re-trial or the prosecution dropped all charges after the conviction was reversed. These are not individuals who received a lesser sentence or who remained guilty of a lesser charge related to the same set of circumstances. All guilt was lifted by the same system that had imposed it in the first place.

Those who argue that some of the exonerated might actually be guilty, either because the jury at the retrial got it wrong or because charges were dropped because evidence of guilt had grown stale, are missing the point.

This notion of innocence, that an individual is innocent unless proven guilty, is a bedrock principle of our constitution and our societal protection against abusive state power. One does not lose the status of innocence merely because a prosecutor or other individuals retain a suspicion of guilt. Of course, it is true that this list makes no god-like determination of knowing exactly what happened in the original crime. Such perfect knowledge of past events is impossible, either to absolutely prove that a person did or did not do an act. We do not try to make a subjective judgment of what we think happened in the crime. We are merely reporting that in a great many cases the justice system convicted an individual and sentenced them to death, but when the process that arrived at that conclusion was reviewed, the conviction and sentence were thrown out. The individual, who often came close to execution, could not even be convicted of a traffic violation. Surely, that should be a cause of concern in applying the death penalty.

Rodricks concurs:

However you shake this, at least 133 people were put on Death Row and slated for execution who should not have been there. These were near-fatal mistakes, in the eyes of our system, way too much imperfection in the area of criminal justice, above all, that requires perfection.

The risk of a wrongful exoneration is trivial compared to the risk of a wrongful execution. When Justice Scalia wrote that “[o]ne cannot have a system of criminal punishment without accepting the possibility that someone will be punished mistakenly," he evinced a willingness to accept that risk. The risk of executing an innocent person is unacceptable in a just society. If even one of the 133 exonerated persons was actually innocent, that's one too many, and it's sufficient proof of the injustice of the death penalty.