CBS) This segment was originally broadcast on Nov. 18, 2007. It was updated on Sept. 12, 2008.
Aside from eyewitness testimony, some of the most believable evidence presented in criminal cases in the United States comes from the FBI crime laboratory in Quantico, Va. Part of its job is to test and analyze everything from ballistics to DNA for state and local prosecutors around the country, introducing scientific credibility to often murky cases.
But a six-month investigation by 60 Minutes and The Washington Post last November showed that there are hundreds of defendants imprisoned around the country who were convicted with the help of a now discredited forensic tool, and that the FBI never notified them, their lawyers, or the courts, that the their cases may have been affected by faulty testimony.
The science, called bullet lead analysis, was used by the FBI for 40 years in thousands of cases, and some of the people it helped put in jail may be innocent.
As correspondent Steve Kroft reports, one of them is Lee Wayne Hunt, who is now serving a life sentence for murder in North Carolina.
Lee Wayne Hunt tells Kroft he's been behind bars for over 22 years and 6 months, and maintains he's an innocent man. "What I've said from the word get go that I ain't -- never killed nobody. I didn't have nothing to do with this," he says.
Hunt was convicted in 1986 of murdering two people in Fayetteville, N.C., based on the testimony of two questionable witnesses and what turned out to be erroneous ballistics testimony from the FBI lab.
For years, the FBI believed that lead in bullets had unique chemical signatures, and that by breaking them down and analyzing them, it was possible to match bullets, not only to a single batch of ammunition coming out of a factory, but to a single box of bullets. And that is what the FBI did in the case of Lee Wayne Hunt, tying a bullet fragment found where the murders took place to a box of bullets the prosecutors linked to Hunt.
"I put it exactly the way it sounded to me, and the way that I believe it to be," Hunt says. "He said that this box of bullets is the same box of bullets that was used to kill these people, made on, about the same time."
"I think everybody in the courtroom assumed that this was valid evidence," says Hunt's attorney, Richard Rosen.
Asked how important he thinks this was to his client's conviction, Rosen says, "I thought it was very important to our client's conviction. It was the single piece of physical evidence corroborating their story. And it came from, you know, it came from the mountaintop."
The FBI first used bullet lead analysis while investigating the assassination of John F. Kennedy, trying to match pieces of bullets discovered at Dealey Plaza with bullets found in Lee Harvey Oswald's rifle.
By the 1980's, the FBI was routinely using this analysis to link bullet fragments found at a crime scene with bullets found in the possession of a suspect, almost always in cases where more reliable ballistics tests were impossible.
"And could you run like a standard ballistics test on this?" Kroft asks William Tobin, a former chief metallurgist for the FBI.
"No," Tobin says. "They're too deformed for the conventional ballistics examinations."
Tobin says the Quantico lab was the only place in the country that did bullet lead analysis, and the assertion that you could actually match a bullet fragment to a specific batch or box of bullets went unchallenged for 40 years -- until Tobin retired in 1998 and decided to do his own study, discovering that the basic premise had never actually been scientifically tested.
"FBI lab personnel testified that you could match these fragments to this bullet," Kroft remarks.
"Yes, that's correct," Tobin says.
Asked what he found out, Tobin tells Kroft, "It hadn't been based on science at all, but rather had been based on subjective belief for over four decades."
"So what you're saying is that this is junk science?" Kroft asks.
"That's correct," Tobin says. "It's worthless as a forensic tool."
Tobin spent months buying and testing bullets and consulting with manufacturers and found that bullets from the same batch weren't chemically uniform, that bullets from the same box didn’t always match, and that it was statistically possible for every bullet manufactured in the U.S. to have tens of millions of twins.
Back in 2002, the FBI lab asked the National Academy of Sciences to conduct an independent review of comparative bullet lead analysis. And 18 months later, its National Research Council came out with a report calling into question 30 years of FBI testimony.
It found the model the FBI used for interpreting results was deeply flawed and that the conclusion that bullet fragments could be matched to a box of ammunition so overstated, that it was misleading under the rules of evidence.
Dwight Adams was the FBI lab director who commissioned the National Academy of Sciences study that ended up debunking decades of FBI testimony, some of which Kroft read back to him.
"Commonwealth versus Daye: 'Two bullet fragments found in Patricia Paglia's body came from the same box of ammunition.' State versus Mordenti, in Florida: 'It's my opinion that all of those bullets came from the same box of ammunition.' Is that supported by the science?" Kroft asks.
"The science never supported such a statement," Adams replies.
"But this was the testimony that was given by people in the lab for 30 years," Kroft points out.
"You know, I'm sure as you have found that that is the case in some cases. But the science does not support that," Adams says. "This kind of testimony was misleading and inappropriate in criminal trials."
A year after the National Academy of Sciences report, Adams decided that the lab would stop doing bullet lead analysis and the FBI notified police departments and the national associations of district attorneys and criminal defense lawyers. The form letters, which underplayed the significance of the problem, said the lab "still firmly supported the scientific foundation of bullet lead analysis," but questions had been raised about its value in the courtroom.
"I've got a copy of the letter that you sent to the National Association of Criminal Defense Lawyers," Kroft tells Adams. "Nowhere in here does it say that the testimony you've been offering for 30 years is no longer valid."
"It's just not in this letter," Kroft says.
"First of all, I don't believe that letter could contain testimonies regarding 100 or 200 or 300 testimonies," Adams replies.
"This letter that you sent never specifically states the testimony offered by the lab, by lab personnel, was wrong. It's just not in here. Yet, you just acknowledged it to me. Why wasn't it in there? I mean, that's a headline grabber," Kroft asks. "I mean, that should be the first sentence of the release, shouldn't it?"
"This review was about the science of bullet lead analysis. And I determined, based upon that review, that it wasn't an appropriate technique," Adams says.
"Did you tell the Justice Department, 'We have this problem and … you ought to undertake a review of these cases?'?" Kroft asks.
"It's not my position to tell the Department of Justice what they should and should not do," Adams says.
Adams says he sent a memo to FBI Director Robert Mueller, stating "we cannot afford to be misleading to a jury" and "we plan to discourage prosecutors from using our previous results in future prosecutions."
But neither the FBI, nor the Justice Department, made an attempt to identify the cases in which flawed testimony had been given, or to notify the defendants, prosecutors or judges involved.
"I think it's a failure on the part of the lawyers at the Department of Justice to own up to a very, very serious error," says Berry Scheck, a director of "The Innocence Project."
The organization has helped free more than 200 wrongly convicted defendants. He says the Justice Department has a legal obligation to notify defendants about any information that might help prove their innocence, even after they have been convicted.
"When federal agents come into court and testify to something that we now know was scientific error that could be crucial, crucial evidence in serious cases … you've gotta go in and make a serious, realistic effort to give people a chance to correct the errors. That's only fair," Scheck argues.
"You can't even begin to talk about raising this issue on appeal if the people involved don't know it happened," he adds.
Only the FBI can identify the cases in which bullet lead analysis was performed, yet it has resisted releasing that information
So 60 Minutes joined forces with The Washington Post to see if we could find some of the cases ourselves. Our producers and Post reporter John Solomon worked with The Innocence Project and a team of summer associates from the New York law firm Skadden, Arps, who conducted computer sweeps of court files.
We managed to identify 250 cases in which bullet lead testimony was a factor, and a dozen where it played a pivotal role in deciding the outcome. And that's after looking at only a small percentage of the total cases.
"There's all together something like 2,500 cases that the FBI analyzed since the 80s. There could be, you know, 30, 40, 50, who knows -- instances where people were wrongfully convicted," Scheck says.
A half a dozen defendants, like a North Carolina pastor who was accused of killing his son-in-law, have already won their freedom or a new trial by appealing bullet lead testimony.
Others, like a Baltimore police sergeant convicted of murdering his girlfriend, and Lee Wayne Hunt, are still in jail.
"I never denied that I was a marijuana dealer in Cumberland County. But I'm denyin' that I ever killed anybody," Hunt says.
"We had fraudulent scientific evidence, that the only concrete evidence that was used in this case, the only physical evidence, was bogus," Hunt's lawyer Richard Rosen tells Kroft.
But Lee Wayne Hunt and his attorney aren't the only ones who believe Hunt was wrongly convicted with bullet lead testimony. At a hearing in January, the case took a strange twist when Staples Hughes, the appellate defender for the state of North Carolina came forward and revealed a secret that he had been keeping for more than 20 years.
"The thing that makes this so terrible is that Lee Wayne Hunt didn't do it. That's what makes it so terrible. He didn't do it. He's not guilty," Hughes says.
Hughes says he's sure of that.
Twenty-two years ago, as a young public defender, Hughes was representing Lee Wayne Hunt's co-defendant in the double murder that sent him to prison for life.
Hughes says his client, Jerry Cashwell, told him in great detail, shortly after he was arrested, how he alone had committed the double murder. Lee Wayne Hunt, he said, wasn't even there. But because of the attorney-client privilege, Staples Hughes was duty-bound to keep the secret.
"It was sort of one of those moments that stops you completely still," Hughes says. "You know, my client's saying, 'Not only did I kill two people, but these other folks didn't have anything to do with it. The state's case is a lie. It's a fabrication.'"
Asked if he tried to get Cashwell to tell that to the authorities, Hughes says, "No."
"I'm his lawyer," Hughes says. "It wasn't in his interest to tell, to have that known at all."
"Because he could have been facing the death penalty?" Kroft asks.
"He was facing the death penalty. It wasn't theoretical," Hughes says.
Asked if this bothered him, Hughes tells Kroft, "It bothered me most when Mr. Hunt was being tried. And it's bothered me ever since. There wasn’t anything I could do about it. But I knew they were trying a guy who didn’t do it."
It wasn't until his client committed suicide in prison that Hughes felt he could come forward to tell his story in court. But instead of being commended for coming forward to clear an innocent man, the judge threw out his testimony and reported Hughes to the North Carolina bar for violating attorney-client privilege, even though his client was dead.
"I'm not too happy to be in the position I am in now," Hughes says. "But there's a guy in prison for somethin' he didn't do."
It's impossible to know right now how many other bullet lead cases like this there may be out there in the netherworld of the criminal justice system. But Dwight Adams, the former FBI lab director who began to have doubts about the science, believes it's time for the government to reveal all of the information.
"I don't believe there is anything that we should be hiding," Adams says. "I believe that everything should be made available in regards to the testimonies and the cases that were worked involving bullet lead analysis."
The FBI ultimately agreed, acknowledging that some of its bullet lead testimony was misleading and that it should have done more to alert defendants and the courts. As a result of the 60 Minutes-Washington Post investigation, the bureau has already reviewed nearly a hundred cases, and according to the Innocence Project there are problems with the FBI testimony in almost half of them.
The complaint against Staples Hughes for violating attorney-client privilege has been dismissed. But Lee Wayne Hunt remains in prison, after the North Carolina Supreme Court refused to hear his appeal.