Scott Louis Panetti is a death row inmate in a Texas prison. Last week, a judge granted a stay of execution because Panetti — who once represented himself in a trial, and called Jesus Christ and the Pope as witnesses — has a history of mental illness.

Panetti was convicted of killing Joe and Amanda Alvarado. Under Texas law, he was sentenced to die by lethal injection. The court determined Panetti's schizophrenia to be no impediment in terms of mental acumen. Last Wednesday, Panetti's attorney Gregory Wiercioch successfully petitioned to reverse the decision — citing the Eighth Amendment's protection against cruel and unusual punishment — and the execution order was suspended.

Medical ethicist Art Caplan called Panetti not only mentally ill but "floridly schizophrenic." "It makes no sense to execute a person like that. I'm not even sure he can fully appreciate the fact that he's being executed," Caplan said Wednesday on Boston Public Radio.

"It doesn't make any sense to me," Caplan said, adding that there are only two reasons to seek the death penalty. "One of them is to deter crime, [and] I don't think this guy would've been deterred. (...) The other is retribution: you deserve it. You did something hard, you should lose your life for it." Caplan said that without either rationale, the death penalty shouldn't be used.

Caplan raised an equally-vexing question for prison medical staff and doctors. "There are people in prison who clearly are mentally ill and who have done awful things. And the question becomes, Should we give them drugs to restore them to at least some level of sanity, and then execute them?" Caplan said that technically, given the proper amounts of medication, those prisoners could be diagnosed "fit to be executed." The power, Caplan said, lay in the psychiatrist's hands.

Caplan noted that prisons have higher levels of mental illness than the population. Some of that population may be better served in a minimum-security facility, or in a mental health treatment center. "A lot of [prisoners] have just brain disorders, and while we certainly don't want them running around getting guns, (...) I think we're going to start moving over to the mental illness model with [hospitalization]. I think the punishment model is going to start to fade as the brain science gets better."

>> Art Caplan is head of the Division of Ethics at NYU's Langone Medical Center. He's the host of the podcast Everyday Ethics.