Three decades and two trials later, Soffar, 57, maintains that he never committed the crimes -- he says he confessed to shooting the two teenagers while trying to implicate someone else in the shootings at the bowling alley, in which three people were killed and another was injured. But Soffar also says he only has faint memories of the interrogation.
The investigators "took full advantage of someone who had no idea of the danger of the situation," Soffar said recently from death row.
Prosecutors said that the evidence against Soffar was solid.
Soffar's lawyers say his case highlights a broader debate about false confessions, and as they ask the U.S. Supreme Court to look at the case, Texas lawmakers are renewing a push to require police officers to record interviews in cases of violent crime.
On July 13, 1980, Arden Alane Felsher, 17, Greg Garner, 18, Stephen Allen Sims, 25, and Tommy Lee Temple, 17, were shot at the bowling alley. Garner survived with severe injuries.
A few weeks later, the police stopped Soffar for speeding and arrested him for driving a stolen motorcycle. On the way to the police station, Soffar said that he had information about the bowling alley murders. "I got involved in something I had no business opening my mouth about," he said in the recent interview. He was charged with the murders after his confession.
Soffar was found guilty of shooting all four people and received the death penalty in 1981, but his conviction was reversed in 2004 when the Fifth U.S. Circuit Court of Appeals decided that his first lawyer had been ineffective. He was convicted again in 2006 and sentenced to death.
Lyn McClellan, who prosecuted Soffar at the 2006 retrial, said that the confession included "information that only the killer would know."
"I think this audiotape is the key to the whole case," McClellan said. "He tells them how this bowling alley murder went down."
Of the police officers who interviewed Soffar, one has since died and another declined to discuss the case. A third, Detective Gil Schultz, said that the confessions were "free and voluntary."
Richard A. Leo, who teaches at the University of San Francisco School of Law and has written several books on police interrogation procedures, analyzed Soffar's tape and determined that officers in the case used verbal techniques like accusation, forceful pressure, repetition and confrontation.
All of these, Leo wrote in an affidavit, "create a risk of eliciting false confessions when misapplied to the innocent." Soffar, sleep-deprived and coming down from drug use, was particularly susceptible, Leo said.
Schultz said that he was kind to Soffar during the interrogation. "I never raised my voice to that man," he said. "I treated him like a human being."
Last Friday, Soffar asked the Supreme Court to determine if the Court of Criminal Appeals, Texas' highest criminal court, has an effective standard for judging whether his trial lawyer, Kathryn Kase, represented him adequately in the 2006 trial. He and his advocates say she should have found an expert like Leo to cast doubt on the confession.
Kase said that her strategy was to introduce news articles that showed that Soffar possibly learned the details of the crime from the news media, but that the judge barred the articles from being presented.
In 2009, the Court of Criminal Appeals upheld Soffar's conviction, though Judge Cathy Cochran wrote that the confessions appeared "to be a tale told by one who heard about the robbery-murders rather than by one who committed them."
Soffar's lawyers said that neither jury was allowed to see evidence that another man, Paul Reid, might have been involved. Reid is now on Tennessee's death row, having received seven death sentences. He lived in Houston at the time of the bowling alley killings.
An employee at the bowling alley said in an affidavit that a man resembling Reid got into an argument with one of the victims and threatened him a week before the killings.
The employee said the police showed him a picture of Reid during the investigation and he identified him as the man who got into the argument.
Soffar's lawyers and Schultz agree that much of the debate over the interrogations could have been avoided if the police had recorded them, though they say that it was not technologically practical at the time.
Now, with inexpensive digital recording, Texas legislators are renewing a push to require the police to record interrogations. According to the National Registry of Exonerations, at least seven wrongful convictions in Texas have involved false confessions.
Sen. Rodney Ellis, D-Houston, has filed a bill requiring the taping of interrogations for violent crimes. Nineteen other states and the District of Columbia currently require such recordings.
Kase, who helped write an earlier version of Ellis' bill, said this was one of many cases that led her to conclude that the police should be recorded so they do not "prop somebody up and record the 'Yes, I did it' statement after hours of interrogation."
Police officers and prosecutors are split on whether recordings should be required. Murray Newman, a former prosecutor in the Harris County district attorney's office, said that police interviews often involve hours of "inane" conversation that precede the confession, and some worry that this material will confuse juries.
Lon Craft of the Texas Municipal Police Association called the requirement "another attempt for the defense bar to find new ways to object to lawfully obtained confessions."
Part of the concern, said Shannon Edmonds, the legislative director of the Texas District and County Attorneys Association, is that in situations where there was no recording, prosecutors might be unable to use a "lawful and voluntary confession" as evidence. His organization has not taken a position on the bill.
Ellis has proposed exceptions to the requirement in cases where a confession is made spontaneously, the taping machine breaks, or the suspect refuses to be recorded. "My hope is that those that have opposed it in the past will come around," he said.
Schultz said recordings would be "fantastic" and could help protect police officers and lawyers from accusations of wrongdoing. But he added that recordings would not have mattered in Soffar's case. "I'm absolutely positive he's guilty," he said.
Brian Stull, a former lawyer for Soffar, said that there would always be unresolved issues in the case, because without recordings "you have to trust what the police officer says."
"They may be telling the truth," he said, "but there are things that could just be lost."
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