Marvin Wilson sucked his thumb into his adulthood, reads at a second-grade level, has an IQ of 61, doesn’t know the difference between left and right, and as a child couldn’t wear a belt without cutting off his circulation.

This evening, he was executed in Texas.

Even though a decade ago the Supreme Court ruled, in Atkins v. Virginia, that low IQ would exempt a defendant from execution, Texas chooses to interpret that decision in a manner that allows them to poison to death defendants like Wilson:

Texas’s interpretation of Atkins isn’t that mentally disabled people can’t be executed; it’s that there’s a threshold of disability at which execution is no longer acceptable.

[…]

Texas’ standards for determining a convicted murderer’s mental competence came from the least scientific document imaginable—a John Steinbeck novel. As the Guardian’s Ed Pilkington explained:

The determinants were posited around the character Lennie Small in Steinbeck’s 1937 novel Of Mice and Men.

“Most Texas citizens,” the argument ran, “might agree that Steinbeck’s Lennie should, by virtue of his lack of reasoning ability and adaptive skills, be exempt” from execution. By implication anyone less impaired than Steinbeck’s fictional migrant ranch worker should have no constitutional protection.

Over the past month or so, there have been intense debates about whether or not I have a right not to carry health insurance, about whether or not the Founders would have put semi-automatic weapons on their Second Amendment list of approved arms, and — of course — about tax exemptions for a presidential candidate’s Olympics-bound horse.

But let’s remember that virtually no one is debating the morality of the death penalty.