For years they sat in prison, convicted of heinous crimes they say they didn't commit. Then a scientific test gave credence to their claims of innocence and, almost miraculously, helped set them free.
From Maryland to Kansas, at least nine defendants -- including two who faced the death penalty -- had rape or murder convictions overturned through a technology known as "DNA typing."
Their release from prison not only changed the public persona of these men, it exposed -- in the view of those familiar with these cases -- the fallibility of a system that purports justice for all.
"It's shaking the false confidence that people once had in the certaintyof convictions," said George Castelle, a public defender in West Virginia, where a DNA case helped uncover widespread misconduct by a state police serologist.
Since DNA typing came into forensic use in the late 1980s, it has been used to assess a suspect's culpability in a crime. From bloodstains, seminal fluid, hair follicles, even saliva residue, scientists can extract the genetic material -- deoxyribonucleic acid (DNA) -- that distinguishes one human being from another and compare it to that of suspect and victim.
A test result can point to guilt or innocence; it can affirm a just verdict or uncover a miscarriage of justice.
In Los Angeles, for example, prosecutors are awaiting the results of DNA typing on evidence seized from the home of O. J. Simpson, who is charged with the murders of his former wife and a friend. The tests can determine within a certain probability whether blood samples from the crime scene match Mr. Simpson's or if blood recovered from the former football star's Ford Bronco came from the victims. The test also can exclude someone as a source of evidence.
The releases of the nine convicted felons since 1991 occurred after DNA typing performed on old evidence -- usually semen stains on clothing -- excluded the men as the source.
The cases not only cast serious doubt on someone's guilt, they raised anew questions about the reliability of eyewitnesses and, in two instances, uncovered evidence previously withheld by prosecutors. Despite these successes on behalf of convicted criminals, those familiar with the justice system say that two factors still prevail:
The overwhelming majority of DNA tests in criminal cases helps convict people in America, and the standard forms of evidence -- including witnesses, ballistics and fingerprints -- remain the mainstay of prosecutions.
Prove people innocent
And yet, there is a small but growing caseload of felons seeking to prove their innocence through DNA typing: Defense attorneys are, for example, pursuing two new cases in Virginia and Wisconsin.
"With this technology, we can prove people innocent in a way we could never do before and look at what in the system creates unjust results," says Barry C. Scheck, co-chairman of the DNA Task Force of the National Association of Criminal Defense Lawyers. "DNA can kind of give you an incredible window, and it indicates how fragile our system is."
But do the post-conviction DNA cases reflect, as Mr. Scheck suggests, a system ill-equipped to identify and analyze its mistakes and the reasons for them? Or are they anomalies in a system that metes out justice fairly in spite of the crush of daily business?
Mr. Scheck, a professor at Benjamin N. Cardozo Law School in New York who has been at the forefront of re-examining old cases with DNA technology, believes that the system doesn't "seriously examine the issue of factual innocence."
'Our error rate'
"People can be convicted if they are factually innocent," said Mr. Scheck, who oversees the Innocence Project, a program at the law school aimed at using DNA testing to identify inmates who may have been wrongly convicted.
"What we have to do is examine scientifically our error rate. If we did, I think there are several other things we would do differently."
Prosecutors and forensic scientists, however, argue that the post-conviction cases coming through the courts in recent years cannot be used to indict an entire system. Since its introduction in criminal cases, DNA typing has also helped to prevent wrongful arrests.
"The technology has increased our investigative arsenal to help us make sure that the person who is being charged and convicted is the right person," said William T. Ferris, a Long Island, N.Y., prosecutor whose office has seen two convicted defendants released because of DNA evidence.
"They [the defense] get a win and they say the whole system is corrupt. They forget the thousands of other cases that come through and it's the right person."
Since the FBI opened its DNA forensic laboratory in December 1988, the bureau has conducted about 2,500 tests a year. About one-third of the DNA typings have excluded the person as a suspect in a case, according to an FBI spokesman.
But the exclusion alone is not necessarily enough to overturn a conviction and win a person's release from prison. Other pieces of traditional evidence such as eyewitness testimony could persuade a court otherwise.
"There has to be a coincidence of events that will ultimately lead to someone's release," said Robert E. Morin, a Washington attorney who represented Kirk L. Bloodsworth, the former death row inmate from Cambridge whose conviction was overturned last year due to new DNA evidence. "It's almost like the eclipse of the sun, everything has to line up exactly."
In several DNA cases, however, the confluence of events that helped free a convicted felon led to other discoveries that defense attorneys say suggest greater, systemwide implications:
* In West Virginia, DNA typing helped Glen Dale Woodall win his freedom from prison after five years, and his case exposed serious misconduct by a former state police serologist. A special report released last fall documented Trooper Fred S. Zain's "long history of falsifying evidence in criminal prosecutions" and identified 134 prisoners who may have been convicted on tainted evidence, not all from Mr. Zain.
Victims contradicted
A previous audit by the state police found "no need" to take any further action on Zain cases, and it was only after a new state police superintendent came aboard that an independent inquiry was convened.
Public defenders are trying to have Zain-related cases reviewed by the courts.
* The releases of Kerry Kotler, of Babylon, N.Y., and Walter "Tony" Snyder Jr., of Alexandria, Va., raised anew questions about the veracity of eyewitness testimony. Mr. Snyder, who had served seven years of a 45-year prison term, received a gubernatorial pardon last year after a DNA test excluded him as the source of semen retrieved from the victim. Mr. Kotler was freed after DNA tests raised doubts as to the source of semen found in the victim's underwear.
The rape victims in each case, however, insisted that both men were their attackers.
* In the cases of Edward A. Honaker, a former security guard serving a life-plus-34-years sentence in Virginia for abduction and rape, and Mr. Woodall, of West Virginia, hypnotists interviewed the rape victims to help them remember the attacks and prosecutors allegedly never told the men's lawyers as required by law. Honaker, whose claim of innocence has been bolstered by a DNA finding, is trying to win his freedom after nine years in prison.
"What's scarier," asked Mr. Morin, the Washington lawyer who represented Kirk Bloodsworth, "that mistakes were made and somebody hid it or no mistakes were made and that's just one of those things? Some people call it the price of democracy. I'm a big believer in our system. But I think people who work in our systemrealize its fraility. It is a system of justice, but it is made up of individuals making human judgments, which can be wrong."
To the extent that DNA typing can improve the system, it will continue to do so, others say.
"The criminal justice system has not been perfect," said Paul B. Ferrara, chief of the state of Virginia's forensic science laboratory and president of the American Society of Crime Laboratory Directors.
"The DNA technology can only do one thing, and that is help increase the percent of guilty people who get convicted and exonerate and reduce the percent of individuals who are wrongfully convicted."
Innocence project
Barry Scheck, the Cardozo law school professor, has spent a good part of the last year using DNA typing to try to prove the innocence of convicted felons. At last count, his Innocence Project had 203 possible cases in its files.
Despite the notoriety of cases like Kirk Bloodsworth and the other freed inmates, prosecutors from Miami to Los Angeles say that they have seen no increase in requests by defendants to re-examine evidence in cases that were concluded before the tests became available in 1988.
"I can speculate why," said Lisa Kahn, the deputy district attorney in Los Angeles who coordinates the use of DNA testing by her office. "The convictions were sound."
William C. Thompson, a lawyer who teaches criminology at the University of California Irvine, believes that the cost of mounting such reviews can be prohibitive. Legal fees alone could run $20,000 to $40,000 if prosecutors fight a request to have evidence tested, he said.
Not all prosecutors have thwarted such efforts.
"As a prosecutor's office we have an interest in ensuring to the public we represent that the people who are in jail are guilty of the crimes they have been convicted of," said Ann Brobst, the Baltimore County prosecutor whose office willingly released evidence in the Bloodsworth case for testing.
In West Virginia, public defender George Castelle has been stymied in his efforts to have DNA tests performed on evidence implicated in the state police serology scandal.
"So people who were convicted on fraudulent data in the first place, who have never had an honest test, are struggling to get tests today," said Mr. Castelle, who is representing 13 defendants in the Charleston area.
But Alexander Ross, coordinator for the West Virginia Prosecuting Attorneys Association, said some prosecutors question the appropriateness of reviewing old cases just because a new technology has been introduced.
Suppose a new polygraph was developed that could determine unequivocally the truth of a witness, he asked.
"Are you going to go back and open up every case that's been decided and put both sides on the polygraph again? You have to say the criminal justice system did the best it could with the scientific knowledge and ability it had at the time."