"He was a drug-dealing tattoo artist who used LSD. I just wanted to be like him," Mr. Dickens remembered. "I was like his dog, you know. Dallas accepted me. He accepted me."

Acceptance assumed supreme importance to a teenager who hardly stood 5 feet tall, whose father had disappeared and whose absentee mother nurtured her son by teaching him to shoplift.

The dealer and the kid enjoyed some fun times, at least until Mr. Dickens – striving to repay a debt to his criminal mentor – shot a beloved high school teacher between the eyes. After that, Mr. Moore was free to move on to other states and additional felonies.

Mr. Dickens went to prison under a death sentence.

His age at the time of the murder – 17 – ultimately placed him among the 73 condemned men hoping for what amounts to a mass commutation from the U.S. Supreme Court.

Today, justices will hear arguments on the constitutionality of capital punishment for crimes committed under the age of 18.

But for that, Mr. Dickens' 10-year-old case would long ago have faded from attention, just another West Texas armed robbery with a bloody and tragic ending. At best, it provided an unnecessary lesson in the stupidity of combining drugs, guns, fear, bad influences and deadly ineptitude.

It also bore the saddest of ironies: He killed the man he should have met.

If only Chicken Dickens had come under the wing of the inspirational teacher instead of the trailer-park crime boss, there might well be one less ill-fated loser in prison today. But that would require the sort of good fortune and youthful application that never attached to Mr. Dickens.

He is 28 now and has spent the last third of his life locked up. His hairline has begun to recede, revealing the image of a hooded executioner inked on his right temple.

"I wasn't a bad person," he said in a recent prison interview. "You may not believe that."

Many don't, including the man who prosecuted him, Randall County District Attorney James Farren: "Justin Wiley Dickens would kill you and your family if you were between him and something he wanted."

Destined to offend?

Instead of inherent malevolence, however, Mr. Dickens' defense attorney saw a pre-ordained doom.

"This kid," Amarillo lawyer Rus Bailey said, "never stood a chance from the day he was born."

The trouble started even before that.

His mother, Vicky Raelene James, decided early in her pregnancy that she didn't want to have a second child. "I used methamphetamine to try to abort," she testified at his 1995 trial.

Released in June from prison for robbery, Mrs. James initially agreed to be interviewed about her son, only to change her mind. Later she agreed again, but changed her mind once more.

"I don't blame her," Mr. Dickens said of his mother's effect on his fate. "She was a good mom when she wasn't high. But she had her own addictions."

Mainly they were heroin and cocaine. She was arrested a dozen times or more; her children were in and out of foster homes. When her son was 10, she tried to commit suicide by slashing her wrists with a broken mirror.

A childhood memory from Mr. Dickens: "Me and my mom started shooting dope [cocaine]. My mom, she would run the streets, shoplifting from stores. She'd steal leather jackets, watches, Monistat, anything. I was basically a decoy. I'd walk around the store and be a distraction."

The paternal side of the family had problems as well. Mr. Dickens' father didn't hang around long, but a stepfather, Geary James, took over.

He could be a doting dad, trial testimony showed, except when he was a doping deadbeat. Once, as Mr. James sat reading a story to young Justin and his sister, members of the Mexican Mafia dropped by to deliver a death threat related to money owed for marijuana sales.

When he was in sixth grade, Mr. Dickens said, "I walked in on my stepdad shooting up in the garage."

(Mr. James is currently serving a prison sentence on drug charges. Earlier this year mother, stepfather and son were all in prison at the same time, though in different institutions.)

By the time he was 14, Mr. Dickens said, he was living on his own. He got the nickname "Chicken," he said, because of his short stature and bantam personality. He huffed gasoline and used LSD. His theft of marijuana from a motorcycle gang earned him a pistol-whipping.

Then he met Mr. Moore, who at age 32 was fresh off a 10-year stretch for first-degree robbery in Missouri.

"He was like a cult figure, an icon," Mr. Dickens recalled. "Me and Dallas became tight."

Mr. Moore gave his new protege a gratis tattoo on his torso – a depiction of a skull wearing a derby decorated with a swastika. When Mr. Moore married his longtime girlfriend, they took Mr. Dickens along on the honeymoon in the bridal suite of an Amarillo motel.

A fraternal bond

"He seemed like the big brother I never had," Mr. Dickens said. "He was a people person."

Somewhere in all this bonding the two of them developed a steady habit of injecting cocaine.

"That's when the bottom fell out," Mr. Dickens said.

It fell hardest when Mr. Moore's wife and Mr. Dickens absconded with a thousand dollars worth of Mr. Moore's cocaine and had a private party. Mr. Moore showed his displeasure by knocking Mr. Dickens around with the barrel of a handgun and demanding repayment.

"He had a ski mask hanging on the wall," Mr. Dickens said. "He pointed to it and said, 'When I get in trouble, I handle my business with a pistol.' "

But Mr. Dickens had no pistol. So he went to his great-grandfather's house, ate some "home-made sticky buns," then strode into the bedroom and secretly lifted a .357.

"The best friend I ever had in the world," he said. "I betrayed him and stole his gun."

An acquaintance drove as he searched for a place to rob. They had been drinking beer, taking Valium and doing coke. Pantera's Cowboys From Hell screamed from the pickup truck's speakers. "Here we come," the song goes, "reach for your gun."

On Amarillo's south side, they stopped at Mockingbird Jewelry & Pawn. Mr. Dickens walked in alone, with the gun in a pocket of his Oakland Raiders jacket. It was 6 p.m. on March 12, 1994.

Two men stood talking at the shop's counter – the owner and a jewelry salesman, Allen Carter of Clayton, N.M.

Mr. Carter was a Vietnam veteran who had grown up dirt poor. "He started working to help support his family when he was six years old," said Mr. Farren, the district attorney.

At age 50, he dealt in jewelry only as a sideline. His real job, and deep calling, was teaching English at Clayton High School.

He had taught there for 23 years, sponsored the student newspaper and was named teacher of the year in 1986. He was the sort of teacher who once took out a personal loan to help a promising former student pay college tuition.

"Allen was just one of those individuals – he was like a magnet," said Clayton principal John Burgess. No one failed Mr. Carter's class, Mr. Burgess said, because he worked with every student – even the most troubled – as much as necessary. "He would not accept failure."

Added colleague Barbalee Blair: "He really, really had a way with kids. He was a fierce, nail-'em-to-the-wall kind of guy who spoke to them in their language."

Then he encountered Mr. Dickens, a junior-high dropout pointing a loaded Smith & Wesson.

"Get on the floor," Mr. Dickens ordered. "Do what I tell you [or] I will kill you."

The shop owner and Mr. Carter complied. This is Mr. Dickens' version of what happened next:

Mr. Carter rushed him and began punching him. Mr. Dickens dropped into a fetal position against the wall. Mr. Carter grabbed for the gun and it went off, hitting him in the head.

The owner of the pawnshop was able to flee. He testified that he did not get a clear view of Mr. Dickens shooting Mr. Carter.

Prosecutor Farren said physical evidence, including blood spatters, did not support Mr. Dickens' account. "It's a lie," he said.

It's also an important legal distinction; if the shooting were accidental, it would not have been capital murder.

Clayton principal Burgess said he can well imagine Mr. Carter trying to persuade yet another wayward youth to turn his life around. "He would try to talk him out of it," Mr. Burgess said. "But he would not try to physically overtake him. That would be out of character."

When news of his brutal death reached Clayton, the students couldn't believe it. "The kids were crushed," Ms. Blair said. "We've had other bad things. But I've never seen them like this."

Back in Amarillo, a friend testified, Mr. Dickens bragged about what he had done. "He thought it was like kind of funny, I guess," she said.

Mr. Dickens has this explanation: "I just felt an incredible sense of shame, and the only way to play it off was act like Mr. Bigshot."

The prosecutor had another interpretation: "He wasn't 'Little Chicken' anymore. He was finally a gangster."

When one of Mr. Dickens' friends turned him in, Mr. Moore, as a veteran of criminal justice problems, had some advice. "He said: 'Take it easy. You're young; you'll be out in 15 years,'" Mr. Dickens recalled. "He said, 'They can't touch you.' "

A decade later, a new generation at Clayton High School walks past an oak tree planted in Mr. Carter's memory. "The kind of kid who killed him," principal Burgess said, "would be the kind of kid that Allen Carter would save."

'Shame and sorrow'

From death row, Mr. Dickens watches as his appeals are slowly exhausted. The most recent denial, in June, came from the federal court in Amarillo. And he was recently diagnosed, he said, with Hepatitis C – not an unlikely occurrence after years of needle drug abuse.

He said he is sorry about Mr. Carter's death but does not believe he deserves lethal injection.

"I feel a lot of shame and sorrow. It haunts me to know that I killed a man," he said. "I know in my heart I'm not a cold-blooded murderer. There are many people who share the blame."

One of those, in Mr. Dickens' mind, is Mr. Moore.

After the murder, Mr. Moore moved to New Mexico, where he turned over a new leaf by committing burglary, kidnapping and jail escape. Now on parole, he gave only a brief interview about the teenager who idolized him.

"He was just a young kid, trying to step up to the plate and trying to impress people," Mr. Moore said. "He got caught."

Such a response doesn't surprise Mr. Dickens. "Looking back, I know he never had no love for me."

But even facing execution, Mr. Dickens can't quite abandon all affection for the one who took him in, no matter how badly it all turned out.

"I still love him," he said. "And I still hate him."