A thick scar snakes around Itchy's neck, the remains of a legendary confrontation when he was serving an earlier sentence at 19. Unarmed and naked in the prison shower, he was attacked by three guys wielding a knife, a razor and an ice pick. By the time guards reached him, Itchy's head was barely attached to his slashed-up body — but two of his attackers were dead, and the third was fleeing. When I met him 30 years later, Itchy, prison boxing coach and law librarian, was a role model for tough old convicts and a magnet for the youngsters. And, for the next 13 years, an invaluable source of insight for me.

Many convicts categorically denounce the death penalty, or any other punishment. A surprising number, however, facing a lifetime inside, become introspective and interested in discussing a subject in which they are undoubtedly well-versed: murder and its aftermath.

Over the years, I have tried to put their opinions and insights in context, to examine them through a coherent moral and legal lens. Seeking to obey the Supreme Court's call for a "reasoned moral response" to the question of punishing murder, I often found myself recalling Itchy's core moral principle: "It's different when you do somebody who's trying to do you" — a variation on the classic "do unto others."

Consider the charge that has put more people on death row than any other — murder in the course of a robbery. Robbery is the most common "aggravating circumstance" that turns murder into capital murder. The conventional reasoning is simple: Life is sacred; property is not. An armed robber seemingly comes prepared to kill over money — in the words of the law, "from a pecuniary motive."

But as the older, professional stickup boys like Itchy emphatically assert, the more important moral distinction to make is whether or not the victim was resisting. The felon who kills a victim who has "bucked a stickup" by pulling a weapon of his own has definitely robbed from a pecuniary motive — but he did not kill from a pecuniary motive.

I've considered this for years — not just from the convicts' point of view, but from the law's. And I have come to believe that, in the context of "capital robbery murder," we should reserve the death penalty for the robber who kills an unresisting victim.

What about the robber who kills to eliminate his victim as a witness? Here the professional lawbreakers mostly concur with professional law enforcers: He's a selfish coward and deserves to die. A robber should "mask down" to hide his identity, they say, or take his chances.

But, then, not all witnesses are alike. Killing an innocent bystander who happens to see a crime in progress is one thing; killing a paid informant who has made a deal with the government is another, the inmates told me. "If you (are) in the army and get captured by the enemy, and you tell where everybody in your platoon is, I feel you need to be killed," explained Itchy. "It's the same thing with us. Whatever you have chosen to be about, you should stick by the code."

It makes sense to me. A felon who has turned state's evidence — who has "flipped the script" — may deserve witness protection, in a world where deals are part of law enforcement. But if that protection fails, his killer should be caged, not executed. There is a code, however perverse, at work: That killer is simply not the worst of the worst.

Let me repeat: I am not saying any murderers should "get off" lightly — they should be locked up for life, and the most vicious among them should be put to death. But the death penalty is too final and profound a punishment to be administered wholesale.

Return for a moment to that "pecuniary motive" aggravator, and consider the hired killer. Most states single out such killers for execution, along with those who pay them. Should they? I put the question to Robert Dent, a former drug lieutenant in his early twenties. Unlike many of the younger convicts I met, he was known for having principles on the street; the older guys said Dent never killed unless he "had to."

"What about a hired killer?" I asked. "What about a guy who will take out anybody? Isn't he different from you? Doesn't he deserve to die?"

Dent considered carefully, but did not agree. "Hit men get paid for what they do," he said. "It's a job with them. It's wrong, but I would respect the person that killed for money more than I would respect the person that's just killing for fun."

Most convicts agreed. Street criminals are among the most ardent capitalists I've met; they believe hard work and effort should and will be rewarded. "Every man's entitled to his own hustle," they say. And: "Society do the same thing we do; they just call it by a different name."

Certainly straight society sometimes rewards people who endanger life from the profit motive: corporate executives — I call them red-collar killers — who maintain lethal workplaces or sell lethal products. We should address that problem. But Dent is wrong. "It's a job" doesn't change the fact that killers for hire deserve to die.

In short, if we want to respond to the high court's call for a "reasoned moral response" to murder, we should revise death penalty statutes to include the aggravating circumstances "killing an unresisting victim," "killing from a pecuniary motive" and "killing to eliminate an innocent witness." Then we could and should drop the grossly overbroad "capital robbery murder" aggravator. The worst of the worst could still get the death penalty; the lesser killers would be sentenced to life in prison.

And bonus, we would largely cleanse the death penalty process of racism: Capital punishment studies have consistently demonstrated that racial bias operates almost exclusively in these "mid-range" murder cases — such as the common murder in the course of a robbery. Refining the aggravating circumstances in those cases would undoubtedly make sentencing less arbitrary, and less prone to bias.