Elaine Sharp is quoted in Lane Wallace’s shallow and amateurish Are All Murderers Mentally Ill? article (which somehow made it into the Atlantic):

You see, I truly believe that murderers are mentally ill. … Their brains don’t work like the rest of ours do. To deliberately kill someone requires crossing a profound boundary. Most of us couldn’t do it. We couldn’t even think about it. But they can. They do. Why? Because they’re mentally ill. And fundamentally, as a society, I believe it is barbaric to kill people who are ill.

(H/T Simple Justice.)

I have never known Sharp to suffer from silliness, but that’s just silly.

If you define “mentally ill” as “doing things that most people don’t do,” then all murderers are mentally ill—as are all geniuses. Even if you add a normative element to the test (“mentally ill people are people who do antisocial things that most people don’t do”), you still paint with too broad a brush, and you add an unscientific “you’re mentally ill because the rest of us agree that you’re mentally ill” component. Mental illness—like any illness—should not be a matter of popular consensus.

Sharp might not be able to think about killing someone, but I’ll bet most of us can. No two people’s brains work exactly alike, but the “profound boundary” of killing someone is one that we were genetically programmed to cross: your genes wouldn’t have survived if some of your ancestors hadn’t been willing to crush a few skulls.

Even in a civilized society, there are times when it is appropriate to cross that boundary. Not all killings are antisocial acts. Not even all killings that the law calls murder are antisocial acts. Most of the murderers I’ve represented, I would allow to babysit my kids (I can’t say the same of the people prosecuting them).

And that’s just the intentional killings. A person can be convicted of murder (and sentenced to death) as a party even if he doesn’t cross that boundary—see, for example, the felony murder rule and the law of parties. (Would Sharp hold that the guy who drives the robbers to the convenience store for the robbery is mentally ill?)

Regular readers know that I’m an incompatibilist determinist: I believe that every action we take is determined by our nature and nurture (themselves determined ultimately at the big pool break at the moment the Universe became). Free will is an illusion; we think  that we have free will in much the same way that the ancients think that Helios drove his chariot across the sky every day.

So I am comfortable with the idea that we do what we do because of pathways in our brains that were wired by forces beyond our control. But “his brain made him do it” is not the same as “he is mentally ill.” If all antisocial behavior is a result of mental illness, all of us are more or less mentally ill; if all of us are mentally ill, “mentally ill” means nothing. And “mentally ill” is a potentially useful term that really should mean something.

Treating criminal behavior as a mental-health issue is a bad idea, not just because it defines the meaning out of mental illness, but also because it allows the government to “treat” it without the Constitutional protections that attach to criminal accusations. It subjects every accused person (every murderer, in Wallace’s world, but why not everyone accused of a crime?) to the tender mercies of consequentialist psychological testimony and proof by clear-and-convincing evidence. Greenfield raises the specter of lifetime preventative incarceration for potential murderers; the mechanisms, I say, are already in place.

I’ve pondered the criminal-justice consequences of my determinism at some length. If I am correct that we behave only as we are programmed to behave, most of the penal goals are still on the table—if bad behavior is a matter of programming, it makes sense for society to correct a bad actor’s programming (specific deterrence and rehabilitation), to correct other people’s programming (general deterrence), and to put the bad actor into a position where he can’t reoffend (incapacitation). Even if the death penalty doesn’t work as a general deterrent, incapacitation might sometimes justify execution.

I would do away with retribution, though, for it seems to me unjust that society should seek retribution against someone for something that he did as the result of his nature and nurture. Sharp calls it “barbaric,” and I tend to agree, but I can see no clear rational reason for society to follow our impulse for justice rather than someone else’s impulse for retribution—as humans, we seem to be predisposed to both retribution and justice, and retribution might be its own good, even if justice be damned. We were, after all, barbarians for a long time before we were civilized.

Wallace wraps up with this:

Or, to put it in Constitutional terms, if someone’s acts are a result of an illness they can’t control, even if the acts are deliberate, conscious and cold-blooded, does it violate the 8th Amendment’s ban on cruel and unusual punishment to condemn them to death because of those acts? It would be interesting to know where Justice Stevens would come down on that one.

Wallace apparently knows nothing about death-penalty procedure: mental-illness evidence that falls short of M’Naghten, as well as evidence of abuse and head trauma, is mitigation evidence in the punishment phase of any competently tried death-penalty case.

Is it cruel and unusual to execute people who are not insane or mentally retarded, but who are mentally ill? Juries often say, “no.” But Wallace, for some reason, wants to know if Justice Stevens agrees. Well, we know already how Justice Stevens feels about the death penalty:

[It] represents the pointless and needless extinction of life with only marginal contributions to any discernible social or public purposes.

[Internal quotation marks omitted.]

Justice Stevens’s position on mental illness in death-penalty cases would be worthy of note only if he thought that executing the mentally ill contributed to some public purpose in a way that executing the mentally healthy did not. I think it unlikely that he would make an exception to execute people who are mentally ill but who fall short of M’Naghten; if he did, I will concede, that would be interesting to know.

It would also be interesting to know that one or more of the sitting Justices thought that mental illness short of legal insanity was, as a matter of law, sufficient mitigation to avoid the death penalty. The Court’s 2006 opinion in Clark v. Arizona gives no hope. It wasn’t a death-penalty case, true, and it was argued on Due Process (rather than Eighth Amendment) grounds, but in Clark six of the Nine were hunky-dory with a murder defendant being sentenced to life in prison when he was not even permitted to present evidence of his (diagnosed) paranoid schizophrenia to negate mens rea.

So no, not bloody likely.