Three years ago, after several prisoners on Illinois's death row had been exonerated, Gov. George Ryan named a commission to study the effectiveness of capital punishment. Scott Turow was invited to serve, not only due to his fame for courtroom thrillers like "Presumed Innocent," but because the former prosecutor had successfully defended an innocent man who had spent 12 years on death row for the murder of Jeanine Nicarico. Three prosecutors in that case were later indicted. Turow's experience on the commission changed his mind about the death penalty, and resulted in his 2002 novel "Reversible Errors," and the just-published nonfiction account, "Ultimate Punishment." We spoke to Turow recently about the morality of the death penalty.

How did the governor's commission convince you that the death penalty was wrong, when the Nicarico case didn't?
You'd think it would have convinced me, but I was still relatively close to my experience as a prosecutor, and I also thought, with prosecutors that wanton, it didn't prove there was something wrong with the death penalty, it proved there was something wrong with the prosecutors. It was only as time wore on in Illinois and Anthony Porter and Gary Gauger and others were exonerated that it started to dawn on me that innocence was actually a problem among those on death row.

How many people in Illinois have been exonerated?
You can look on the Death Penalty Information Center for the latest number. Last time I looked, we've executed 1500 people and exonerated 108--that means legally absolved. There are also dozens and dozens of cases where the charges were resolved without a formal finding that they were baseless. I've never been under the illusion that everybody on death row is innocent-far from it. My own guess is upwards of 90 percent are guilty. But a ten percent error rate if that's what it is, or even five percent, is really way too high.

Have you met any of the death row inmates who have been exonerated and released?
Sure, many of them.

I'm always amazed at how forgiving they are.
It really varies from guy to guy. A lot of them develop a sense of religious belief. Imagine if you were sitting in a prison cell for ten years, asking."Why is this happening?" You've got to believe that somebody has a reason for this, and it's certainly not a human one. But both the degree of recovery and range of response varies. Obviously, in the abolitionist community they want to present everyone as a Christlike martyr. I think to some extent that's p.r.

Did your religious background affect your feelings on this issue?
I'm of that generation of Jews still deeply influenced by the Holocaust. Certainly the notion that the state power to kill can be subject to such extraordinary abuse is always lurking beneath the surface for me. Certainly my experience and identity as a Jew is there. I wouldn't say religious training contributes a lot. A rabbi was upbraiding me for claiming that the Yahweh of the Old Testament is a wrathful God. With all due respect to the rabbi, I think he's wrong. I think that's a fair view of most of what that God is up to.

So is capital punishment revenge?
It's subtly different than revenge. I always laugh when people say, "It's not just revenge." That's a religious attitude among those who have been taught to turn the other cheek. Revenge obviously plays a large part in punishment. Prisons wouldn't be as stark and awful as they are if we didn't want a measure of revenge. If we were just trying to keep them off the street, they could live in college dormitories.

So what are we doing when we sentence people to death?
I think to most Americans it's a statement of values. For ultimate evil there has to be ultimate punishment. Certain behavior--McVeigh, John Wayne Gacy, the Beltway Sniper--is so far beyond the bounds of what can be tolerated in any civilized society that we have to demand the highest price imaginable. That's the argument: to do less demeans the value of life and what it means to live among each other.

Do prosecutors become calloused to the value of life? Is that how they come to push for death even when they have the wrong person, as they did in the Nicarico case?
I don't think the Nicarico prosecutors can be confused with all prosecutors. To an extraordinary extent we are still sheltered from the reality of what goes on. Sitting in the back of a felony courtroom in Chicago, you hear stuff that blows your mind. You've got routine drug deals that are to some extent explicable and understandable. But the student who goes in to the nun who taught him and pours lye down her throat, or the father who takes his house keys and puts out his child's eyes-these are people who have been raised in hideous circumstances that have taught them no sense of human attachment who behave that way. They don't have feelings for other human beings. They can be cruel in ways that it's hard for you and me to imagine.

But my own estimate is that the prosecutors in the Nicarico case had the normal impulse of cops and prosecutors when they make a mistake. They were anxious to respond to community pressure to find these horrible killers. It's their job and they want to believe they can do it and do it well. What bothers me about what happened in DuPage County is that eventually it became a matter of political survival. Political ambition becomes entwined with not telling the truth.

So the nature of death penalty cases themselves breed that disregard?
I think there is an inherent paradox in capital cases. The death penalty is supposed to be reserved for the worst of the worst, but it's the sniper cases and the Nicarico cases that are most likely to go wrong. Fear, revulsion and wrath all undermine our ability to deal with these cases rationally. So you say, "I got these two who committed this murder and goddamnit I'm going to prove it." And lo and behold, you end up with two innocent men spending 12 and a half years behind bars. And they are hardly unique.

What about the survivors? Don't the victims' families deserve satisfaction?
Well, the question is what is satisfaction? There has never been any study of whether an execution grants closure, or emotional relief of any kind. I suspect that they want the world put back to the way it was. That's a fantasy that will never be fulfilled.

But even accepting that executions provide some kind of emotional relief, that's not the end of the analysis. That's not a privilege we pass out to all victims. We execute only two percent of homicide offenders in Illinois. Most of the time we disregard retributive wishes. Prosecutors say for whatever reason, because the defendant's willing to plead, or because of the gravity of the offense, or because we tried a big death penalty case and the county doesn't have the budget to do two of them, we're not going to grant your wishes in this case. We use victims as a fig leaf. We're really talking about the prosecutors' and the cops' and the public's wrathful impulses. It's a much more convenient wrapper to say that's what the victims want than to confront our own bloodthirstiness.

Your arguments are largely based on problems with the system. But strictly as a moral question, is it wrong to trade death for death?
When we talk about the death penalty we're talking about abstractions. But recognize what you're actually talking about doing. If we had a judge and a jury who just happened to arrive at the scene as a murderer's finishing the person off, that's one kind of morality. But what's happening now is you make a guy live for 10 or 12 years telling him you're going to kill him. Then you make him take that walk, knowing with a certainty that few human beings ever have that they are about to die. Then you strap them down in front of an audience. And then you kill them. And you kill somebody who in most instances has been rendered docile by the restrictive environment in which they are locked up. The one thing that really came over me is the unbelievable cruelty of doing that.

I do not judge the people who do that on behalf of the state. If it was Gacy on the gurney and life's circumstances that had put me in that position, I could push the button. But I would do it knowing that society had commanded a really dreadful act.

Did writing novels give you a bigger picture about this?
Writing "Reversible Errors" did. The perspective of that novel came to influence my deliberations about the death penalty, to this extent: what we want is an end to the extraordinary anxieties murder produces. Murder, if unchecked, would reduce ordinary civil life to war. We want the world to be restored. We look at the law and say, "Restore the world." The fact is, the law alone can't restore the world. Our sense of a restored world really resides more in our connections to each other.

"Reversible Errors" is about the limits of the law to define who committed ultimate evil, to define what ultimate evil is, to allow the million arbitrary factors to make this a meaningful punishment, and finally to say are we really accomplishing what we wanted to accomplish? Are those anxieties relieved? I don't think so.