Robert Hughes was a Vietnam veteran with a long criminal record and a history of heroin addiction.

He was also the prosecution’s star witness at the trial of Bruce Lisker, a San Fernando Valley teenager accused of beating and stabbing his mother to death.

Hughes told the jury in the fall of 1985 that Lisker had been in the cell next to his at the Los Angeles County Jail, and that the two had spoken through a 4-inch hole in the wall.

“He told me that he killed his mother,” Hughes testified, “and then he started telling me how.”

Lisker was convicted and sentenced to life in prison. Today, much of the case against him has been discredited by new or previously overlooked evidence. As Lisker fights to overturn his conviction, Hughes is once again at center stage. His testimony is one of the last surviving elements of the prosecution case.

Now it, too, seems suspect.

An examination of his past has found that:

• Hughes has a history of mental problems that was not known to participants in Lisker’s trial. Doctors have diagnosed him as a paranoid schizophrenic suffering from severe post-traumatic stress disorder. He has reported hearing voices and once believed Viet Cong were tunneling beneath his house.
• In an 18-month period in 1982 and 1983, Hughes reached out to authorities three times to report that accused murderers had confessed to him. He testified against all three defendants, and was rewarded with a reduction in his own sentence. In two of the cases, his testimony was at odds with physical evidence.
• A detective who used Hughes as an informant grew leery of his knack for producing confessions. The detective said he warned Hughes not to become “a professional informant” because no one would believe him. Soon after, Hughes came forward with Lisker’s alleged confession.
• After Lisker’s supposed admission, Hughes wrote him letters in jail in which he expressed confidence that the teenager would soon be freed. On the witness stand, Hughes suggested that the letters were forgeries. The prosecutor conceded to the jury that Hughes was indeed the author.

Lisker, now 40 and an inmate at Mule Creek State Prison southeast of Sacramento, has filed a habeas corpus petition in federal court, contending that he was unjustly convicted.

In July, a federal magistrate judge ruled that Lisker had made a persuasive preliminary case that he is “innocent of the crime for which he has been convicted.” The magistrate ordered an evidentiary hearing, scheduled for December, to explore the issue further.

Hughes is likely to play a key role. Lisker’s lawyers say information discovered by The Times about Hughes’ mental condition is new evidence that further undermines the prosecution case.

They also contend that Hughes, given his history as an informant, was essentially an agent for the prosecution whose conduct violated Lisker’s right to a fair trial.

The state attorney general’s office, however, says Hughes’ testimony about the confession remains persuasive evidence of Lisker’s guilt. Prosecutors have listed him among the witnesses they will call at the December hearing.

Hughes, who now lives in Utah, said in a recent interview that he testified truthfully in 1985. But he said he understood why his credibility might be questioned, and he acknowledged doubts about Lisker’s guilt.

“If all they’re going on is my testimony,” he said, “that wouldn’t be enough for me.”

Words of Comfort

Dorka Lisker, 66, was bludgeoned and stabbed to death in her home in Sherman Oaks on March 10, 1983. Her adopted son, Bruce, then 17, called for an ambulance.

The teenager had a history of abusing drugs and fighting with his mother, and his hands were covered with blood when police officers arrived.

He said he had come home to find the front door locked and had walked to the back of the house, where he looked through a window and saw his mother’s body on the floor. He said he broke in, rushed to her side and administered first aid.

Police dismissed Lisker’s account as a fabrication. They believed he killed his mother after she found him stealing money from her purse. He was charged with murder.

A judge ruled that Lisker should be tried as an adult, but ordered him held in juvenile hall.

Three days later, in violation of the order, the youth was moved to the Men’s Central Jail in downtown Los Angeles. He was placed in a segregation area for youthful offenders, informants and others who would be at risk in the general population.

At the time, sheriff’s deputies, who run the jail, sometimes deliberately placed suspects among known informants.

In the guise of wanting to help, snitches would pump cellmates for information about the charges and evidence against them. Then they would fashion “confessions” based on what they learned, a grand jury reported years later.

The informants would testify for the prosecution in return for early release or a reduction in their own charges. Prosecutors used informants’ testimony, much of it suspect, in as many as 250 cases from 1979 to 1988, the grand jury said.

Within weeks of Lisker’s transfer, two men in the cell next to his told authorities that the teenager had admitted killing his mother. But the confession they recounted did not fit the facts. Detectives dismissed the two as liars.

Hughes, then 29, was in a cell on the other side of Lisker’s. By his account, he befriended the boy by posing as a concerned Christian and whispering words of comfort through a hole in the common wall.

With a Bible in his hand, he asked Lisker if there was anything he wanted to get off his chest.

‘He’s a * Liar!’

Hughes grew up in public housing in Pacoima, one of nine children. As a teenager, he dropped out of school, began using drugs and had numerous scrapes with the law.

In 1971, at age 17, he joined the Marine Corps and went to Vietnam. He served as a machine gunner in a combat platoon.

“I shot everything that moved,” Hughes said. “Even monkeys.”

After three years, he left the service with an honorable discharge and an addiction to heroin. Back home, he committed burglaries to support his habit. By late 1981, he was bouncing between the Los Angeles County and Orange County jails, charged with car theft, assault with a deadly weapon and other offenses. In January 1982, he agreed to a plea bargain and was sentenced to five years. As he waited to be transferred to state prison, Hughes told his Orange County jailers that he needed to talk to the district attorney — not about his case, but about a former cellmate named Richard Crowell.

Crowell was accused of killing his girlfriend’s husband with a .357 Magnum while the victim slept on a couch. Hughes said Crowell had confessed to the crime.

Hughes was willing to testify but wanted something in return: a reduction in his sentence. Prosecutors said they would try. Hughes took the witness stand three months later and told jurors that Crowell had admitted to the murder.

The trial ended in a hung jury. Facing a possible retrial, Crowell pleaded no contest to voluntary manslaughter and was sentenced to 10 years in prison.

This July, a shirtless man covered in prison tattoos answered the door at a Long Beach apartment complex where Crowell was believed to be living.

At first, the man denied he was Crowell. When a reporter mentioned Hughes, he dropped the ruse and erupted in a string of expletives.

“Robert Hughes!” Crowell blurted out. “He’s a * liar!” Crowell said Hughes was friendly and talkative during the two months they shared a cell. “He was full of questions,” Crowell recalled. “The first thing he asked me was ‘What are you in for?’

“I was a dupe. A sucker. Now I know.”

Key Fact Is Wrong

As he was working with Orange County prosecutors on the Crowell case, Hughes reached out to Los Angeles authorities to report a second alleged murder confession.

This time, Hughes said another cellmate — Bernard Milberger Jr. — had admitted fatally shooting an elderly clerk during a 1981 liquor store robbery in Pasadena.

At first, authorities were not interested. They already had an informant lined up to testify that Milberger had confessed to the crime while in jail.

But when that witness disappeared, detectives needed Hughes. They flew to the state correctional institution in Tracy, where he was serving his sentence, and brought him back to Los Angeles.

Again, Hughes wanted a break on his sentence, which he had yet to receive despite his earlier cooperation. Again, prosecutors promised to do what they could.

When Hughes offered to testify about yet another murder confession, Los Angeles County Sheriff’s Det. Frank Salerno cut him short.

“I told him, ‘I don’t want you involved in any other cases,’ ” recalled Salerno, now retired. “ ‘I don’t want you becoming a professional informant. The more cases you get involved in, the less people are going to believe what you’re saying.’ ”

On the witness stand, Hughes said Milberger confessed to him when the two were in the showers one day at the L.A. County Jail.

But Hughes could not remember details of the alleged confession that were in his original statement to police. And he got a key fact wrong: He testified that Milberger had admitted to shooting the clerk in the head. The victim was shot in the torso.

In cross-examining Hughes, defense attorney Ronald Hauptman said his testimony sounded suspiciously like that offered at a preliminary hearing by a witness who later recanted. That witness, the girlfriend of Milberger’s accomplice, said Milberger shot the clerk. Later, she admitted that she had lied to protect her boyfriend.

Hauptman suggested that Hughes had fabricated his story after reading a transcript of the girlfriend’s testimony. The lawyer also suggested that it was not the first time Hughes had manufactured a confession by reading documents about a fellow inmate’s case.

Hauptman said a prisoner had described seeing Hughes read police reports on Richard Crowell’s case before he testified against Crowell.

Hauptman, now a Superior Court commissioner, said in a recent interview that Hughes was a transparent liar. “He was so sleazy that it made it appear as if the D.A. was grasping at straws,” Hauptman said.

Nonetheless, Milberger was convicted of first-degree murder and sentenced to life in prison. Two years later, an appeals court cited his alleged confession to Hughes as a reason for upholding the conviction.

In a recent interview at Salinas Valley State Prison, Milberger denied confessing. He said another inmate had warned him that Hughes might be a snitch, so he watched what he said. Milberger said he suspected that Hughes read the preliminary hearing transcript while he was alone in their cell. “He knew how to set people up.”

‘He Was Slick’

The case against Lisker presented a challenge for Deputy Dist. Atty. Phillip H. Rabichow. He could place the teenager at the crime scene with his mother’s blood on his hands and clothing. But there were no witnesses, and the physical evidence was ambiguous. So Hughes’ emergence was a welcome development. The confession he claimed to have heard tied the dry pieces of evidence into a narrative easy for a jury to grasp.

In a tape-recorded statement to detectives in July 1983, Hughes said Lisker had told him that he fought with his mother over money and then attacked her with an exercise bar, a Little League trophy and two steak knives — details consistent with police reports and the police theory of the crime.

Hughes agreed to testify on condition that Rabichow follow up on prosecutors’ earlier promises to seek a reduction in his five-year sentence.

Rabichow agreed. In a letter to a prison official, he described Hughes’ testimony against Crowell and Milberger as “critical.” A judge released Hughes from prison in December 1983, nine months early.

At Lisker’s trial nearly two years later, defense attorney Dennis E. Mulcahy called attention to Hughes’ career as an informant and questioned his motives.

“Every time you came forth with information, you always expected something,” Mulcahy asked.

“Yes,” Hughes replied.

Mulcahy pressed Hughes for details about Lisker’s alleged confession. Hughes said the teenager made the admission during their first conversation.

“Let me understand this,” Mulcahy said. “Bruce never knew you from anywhere and Bruce told you he wanted to confess to you?”

Mulcahy also confronted Hughes with letters he wrote to Lisker in jail after the supposed confession.

“I feel you are going to the streets soon,” said one.

“The Lord gives me a strong feeling you will be out of this pit soon,” read another.

Asked why he would say such things to someone who had just admitted to a murder, Hughes said he didn’t think he wrote the letters.

“Do you have any trouble recognizing your own handwriting?” Mulcahy asked.

“It seems like it is easy to copy,” Hughes replied. “I know there are professional artists at this.”

Rabichow later acknowledged to the jury that Hughes wrote the letters.

Mulcahy also seized on an aspect of Hughes’ account that seemed at odds with the physical evidence.

Hughes said Lisker admitted to him that he had lied when he told police he entered the house through a window after seeing his mother’s body on the floor. Hughes said Lisker told him that, in fact, he removed the louvered panes of a kitchen window after attacking his mother — to support his cover story.

But, the defense lawyer noted, no blood was found on the windowpanes or on a pair of pliers that Lisker used to gain entry — even though his hands were bloody.

“If Bruce set up this alibi, why no blood on the pliers?” Mulcahy asked during his closing statement. “Why no blood on the screen?”

There was no mention during the trial of Hughes’ mental problems, which date to the late 1970s but were not diagnosed and documented until years after Lisker was convicted.

Rabichow, now retired, said he believed Hughes was truthful because he knew details of the crime that could only have come from Lisker. He declined to comment further, saying he expected to be called as a witness at Lisker’s forthcoming court hearing.

Mulcahy, now a Superior Court commissioner, also declined to comment.

Lisker said he never confessed to Hughes. The older inmate, he said, concocted his account based on their conversations and on police records that he shared with Hughes through the hole in the wall.

“He was slick,” Lisker recalled. “He said he could help me. I was naive.”

Erratic Behavior

After getting out prison, Hughes moved to Big Bear, married and started a successful construction company. He bought a BMW sedan, two Harley-Davidson motorcycles and a Piper Cherokee plane, which he flew to Laughlin, Nev., to play the slot machines.

Then the real estate market tanked in the early 1990s, and Hughes declared bankruptcy. A court revoked his protection from creditors for allegedly hiding cash and other assets.

Hughes’ behavior became erratic. He ignited a homemade explosive beneath his house, court records show. In a recent interview, he said he believed at the time that Viet Cong were living in tunnels under the house.

Police arrested him for being in possession of a Ruger semiautomatic rifle, an illegal act for a convicted felon. Later, people who lost money in his construction business accused him of fraud.

One investor, a retiree named Clifford Swires, told an investigator that Hughes left him a check for $60,000 shortly before Christmas 1994, along with a note of apology signed “Robert the robber.”

When Swires tried to cash the check, he said, he learned that the account had been closed for two years.

Hughes fled to Boise, Idaho, with a girlfriend. There, he sought help at a Veterans Affairs hospital in March 1995. He said he was hearing voices and having “peculiar thoughts,” records show. Doctors prescribed Risperdal and Depakote, powerful antipsychotic drugs.

A few months later, Hughes stopped taking the medications and heard a voice commanding him to go to Canada. He set out on foot, walking 35 miles without water, records show.

In July, he was back at the VA hospital. Doctors diagnosed him with post-traumatic stress disorder and schizophrenia. They put him back on his medications and released him after a week.

Soon after, California authorities learned that Hughes was hiding in Idaho and arranged to bring him back to stand trial on the weapons charge.

Michael E. Kania, a court-appointed psychologist in San Bernardino, found Hughes to be delusional and recounted his long history of mental problems.

“He reports being bothered by intrusive thoughts that he has experienced over a number of years, in addition to auditory hallucinations which he experienced following his stay in Vietnam, first experiencing them when incarcerated in 1977,” Kania wrote.

Hughes believed that people could read his mind and that unknown forces were trying to communicate with him through radio broadcasts and coded messages on license plates, the psychologist wrote.

Hughes’ girlfriend told Kania that Hughes had hallucinations that “Jedi knights” were trying to contact him.

Hughes pleaded guilty to the weapons offense, diversion of construction funds and fleeing prosecution. He served six years in prison and was freed on parole in 2001.

San Bernardino County Deputy Dist. Atty. Michael Abacherli, who prosecuted Hughes, remembers him as “a personable guy” who told the truth when it was convenient.

“I would not call him a pathological liar. I would call him a con man,” he said. “If he wanted to accomplish something that couldn’t be accomplished by telling the truth, he would lie.”

Told of Hughes’ role in the Lisker case, he said: “I would be highly skeptical. That sounds exactly like a scenario that Mr. Hughes would try to take advantage of.”

‘I Heard What He Said’

Aside from the prison tattoos that cover both his arms, Hughes bears little resemblance to the wilder man of decades past.

At 51, he appears to have outgrown the criminal life.

He lives with his third wife, Sharon, in a comfortable home on a hillside in Cedar City, Utah, in the high desert near the spectacular cliffs and canyons of Zion National Park.

Living on a VA disability pension, he spends his days doing chores around the house and working in the yard. He rides a mountain bike and fishes for brown trout.

In May, two reporters knocked on his door and asked to talk to him about new findings in the Lisker case.

Among other developments, recent police and FBI analysis of a bloody footprint from the crime scene had showed that it was not made by Lisker’s shoes, contrary to what the prosecution said at the trial.

In addition, a police review of old autopsy photos had found an impression on the back of Dorka Lisker’s head that appeared to match the mystery footprint.

The discoveries suggested the presence of an assailant other than Bruce Lisker. Rabichow, the prosecutor, said he now had “reasonable doubt” about Lisker’s guilt.

Hearing this, Hughes grew agitated and told the reporters he had nothing to say. Then, sharing sodas with his guests on his front porch, he slowly relaxed and opened up. Over six hours of conversation that day and the next, he was by turns regretful, defiant, elusive and contradictory.

At first, he was adamant that Lisker had confessed. “You can show me all the footprints you want,” he said, chain-smoking hand-rolled cigarettes. “But I’m beyond a shadow of a doubt. I looked in his eyes. I heard what he said.”

Later, Hughes retreated slightly. He said he was certain about what Lisker had told him, but not certain that it was true. He said Lisker might have been playing the “tough guy” to impress fellow prisoners.

He went on to say: “If Rabichow has doubts, then so do I.” And later: “I’ve said some deep prayers about this. If the guy’s innocent, get him out.”

Hughes expressed remorse that he had used religion to gain Lisker’s confidence. He said he had been desperate to get out of jail and saw the teenager as his ticket out.

“I was being more of an informant than I was a minister,” he said. “That’s the hypocritical, terrible thing I feel about myself.”

At times, Hughes seemed to want to appease Lisker and his lawyers. He suggested that they should be satisfied with his expressions of doubt, however fleeting and equivocal they were. And he said he would give no further testimony in the case.

“They can count me out,” he said, unaware that prosecutors would list him as a witness for Lisker’s forthcoming hearing.

His reluctance to appear in court did not mean that his earlier testimony was untruthful, Hughes hastened to add. “The bottom line is that they all did confess,” he said of Lisker, Crowell and Milberger, “and I’d be lying if I said they didn’t.”

Asked what it was about him that had prompted three accused killers to admit their guilt, Hughes broke into a broad smile.

“I have no idea,” he said. “You have anything you want to get off your shoulders?”