The state of South Carolina on Friday strapped down Freddie Owens and injected him with a chemical that’s usually used to euthanize pets.

In the days before the execution, a key witness against him admitted testifying falsely at trial to save himself, and said Owens had nothing to do with the 1999 murder for which he was convicted. But that didn’t matter. Owens, also known as Khalil Divine Black Sun Allah, was put to death.

Officials in Missouri executed Marcellus Williams this week. The two witnesses against him are known liars, and the bloody footprint and hair samples found at the scene were determined not to belong to him or the victim in the 2001 fatal stabbing for which he was convicted. DNA samples on the murder weapon haven’t been analyzed because prosecutors handled the knife without gloves and tainted the evidence. A Missouri governor stayed an earlier execution and ordered a board to investigate the case. But a new governor dissolved the board and revoked the stay.

Earlier this month the prosecutor offered to switch the sentence to life in prison if Williams would plead guilty, and the condemned man agreed despite insisting he had nothing to do with the crime. A judge accepted the deal, but it was thrown out on appeal. So despite the lack of physical evidence linking Williams to the murder, and over the objection of the prosecutor and the victim’s family, he was executed.

Death sentences and executions, even for actual murderers, are relics of primitive societies in which leaders and their underlings ritually killed to expiate perceived evil, propitiate the gods and calm fears of social chaos.

So what do death sentences become when the witnesses, police, prosecutors and judges admit that their former testimony or conclusions were wrong and the accused is innocent, and the executions proceed anyway?

They cross the line that separates civilization from savagery, criminal justice from black magic, accountability from ritualistic human sacrifice. They become false religion, dependent on totems such as “shaken baby syndrome,” and shamanistic revelation — for example, the suspect looked guilty. They promulgate superstitions, such as the magical pretense that the killing deters future crime. They satisfy our primordial demand for guilt and punishment and our illusion of moral cleansing.

What they cannot satisfy is the delusion that our society is just and merciful. The appetite for blame and blood is voracious and repeatedly beats back our aspiration to be a more enlightened, humane and modern nation. President Joe Biden, soon to leave office, promised as a candidate he would do away with federal death sentences but has not acted.

Former President Donald Trump, seeking reelection, last week reiterated his long-standing demand to quickly execute drug dealers.

But even when we kill the guilty, we become needlessly cruel. When we kill the conceivably innocent, we become a mockery of ourselves and our supposed allegiance to justice.

— The Los Angeles Times