Welcome to Amicus, Slate's new legal podcast. I'm Dahlia Lithwick's late Supreme Court correspondent.

In 2007, the U.S. Supreme Court heard a case called Panetti v. Porterman.

It raised a lot of questions about whether a man who was convicted of a murder in Texas, a man by the name of Scott Panetti, was just too mentally ill to be put to death.

So here's a back and forth from that oral argument between Panetti's lawyer, Greg Weirchuk, and Chief Justice John Roberts.

Could you maybe elaborate on that? I mean, if you have someone who is competent at the time they're convicted,

competent at the time they're sentenced, and I mean, you say they're walking to the gurney to be

executed, you know, they fall and they hit their head and then they don't understand it,

it's somehow very cruel to go forward with the execution at that point while it wouldn't have been before?

It seems to me, I mean, obviously, the competence at trial and sentencing is important.

I just don't understand the concept that it has to continue to the point of execution.

I think that's the very nature of the Ford right, that it is something that intervenes.

We're not saying that Scott Panetti was not fully culpable, found guilty, a sentence

to death.

We're not attacking that at all.

Something happened.

And what happened is he did lose the ability to understand

rationally the connection between his...

What does he understand why he's being imprisoned? I mean, does this, the Ford Wright extend to prison?

Is it cruel to keep someone locked up for life when they don't understand why they're being locked up for life?

In the end, the Supreme Court sent this case back to the Texas courts with instructions to look

much more carefully into the question of whether Panetti's schizophrenia and delusions simply

made him ineligible for the death penalty. But the lower courts, after doing so, determined

...