When the 57-year-old Alzheimer's victim came home from day-care at a Tacoma, Wash., hospital, her disheveled clothes made her daughters suspect that she had been raped. Their fears were confirmed when a medical examination of the woman, who remembered nothing, showed semen.
Law enforcement officials immediately had a suspect: Alan J. Haynes, 34, the day-care center's van driver. He was the only man who had been alone with the woman.
But there were no witnesses or fingerprints to link him to the crime.
So authorities sent a semen sample taken from the woman and a blood sample taken from Haynes to a laboratory for a controversial type of analysis called genetic fingerprinting. Using sophisticated genetic engineering techniques, forensic scientists compared the deoxyribonucleic acid (DNA) in the sperm to DNA from Haynes' blood and found them to be identical.
Confronted with this evidence, Haynes pleaded guilty in December, according to Pierce County deputy prosecutor Barbara Corey-Boulet. Haynes is to be sentenced Jan. 29.
His case is among a handful in the United States in which genetic fingerprinting, developed only about two years ago, has been used to prosecute a criminal suspect. But the number of cases is increasing steadily and experts believe the technique's unique capability to identify a perpetrator with virtual certainty will ensure its wide use in the future.
The technique is a significant advance over fingerprinting or matching blood proteins. The latter approach, because of its lack of specificity, can only exonerate a suspect or show that he may have committed the crime.
"It's a giant step forward," said Barry Albert, an Oklahoma County, Okla., assistant district attorney who intends to rely on evidence obtained by the technique in a rape trial scheduled to begin on Monday.
But the increasing use of genetic fingerprinting is also raising questions about the reliability of the technique and about the ability of police laboratories that may eventually use it.
Even before the technique came along, many such laboratories already were being criticized for hiring poorly trained personnel and for sloppy handling of evidence. Now critics fear that such personnel would not be able to adequately perform the sophisticated techniques required for DNA analysis.
Criminal defense attorneys also argue that prosecutors may be moving too fast by introducing genetic fingerprinting evidence in trials before its reliability has been thoroughly established.
"I don't think we've satisfied all those demands yet," conceded Cecil Hider, manager of the California Criminalistics Institute, part of the state Department of Justice in Sacramento.
"We are very concerned that some jurisdiction (in California) will prematurely introduce genetic fingerprinting results and establish bad case law that might adversely affect future cases," Hider said.
To reduce this possibility, the Department of Justice is bringing together criminologists and prosecutors from throughout the state for a meeting today at the Los Angeles Airport Marriott to discuss use of the technique.
"Nobody has seriously challenged the admissibility of DNA analysis yet," Hider said, "but it's certainly going to happen. We want to have all our bases covered when it does."
Most forensic techniques, such as fingerprinting, blood typing and hair analysis, have gradually gained acceptance in the courtroom. But others, such as the polygraph, remain controversial.
So far, trial courts have accepted evidence obtained by genetic fingerprinting in the few cases that have been tried. As yet, no prosecutor in California has attempted to introduce such evidence in a criminal trial.
Genetic fingerprinting was developed in 1985 by geneticist Alec Jeffreys and his colleagues at the University of Leicester in England. Jeffreys found that DNA--which serves as a blueprint for all living organisms--contains many short regions that are unique in composition and size for every human except identical twins.
Jeffreys then developed a technique that, in essence, involves extracting the DNA from a specimen of blood, semen or tissue and chemically chopping the DNA into short fragments. When the fragments are separated by a technique called electrophoresis, they form a unique pattern that serves as an identity profile.
That pattern can then be compared with the pattern from a criminal suspect's blood--which, in most states, is routinely obtained, with a court order if necessary. The odds that such genetic fingerprints from two individuals will be identical range from one in 200,000 to one in 30 billion, depending on the number of fragments compared.
In comparison, the odds that conventional fingerprints from two individuals will be identical are about one in 64 billion. "But a suspect can always argue that a fingerprint was left when he was at the crime site on legitimate business," said forensic scientist Ed Blake of Forensic Science Associates, an Emeryville, Calif., consulting firm. "Finding an individual's biological sample at the site of a violent crime is much more (convincing to a jury)," he said.
Paternity, Maternity Cases
Genetic fingerprinting is also being used to prove paternity or maternity in civil cases. The genetic fingerprinting process takes about two weeks, and the cost is between $200 and $300 per sample, only slightly more than the cost of blood typing.
The first uses of genetic fingerprinting were in immigration cases.
One such case involved a Ghanaian boy who was born in England and then emigrated to Ghana to live with his father. When the boy subsequently attempted to return to England to rejoin his mother, brother and two sisters, British authorities denied him permission to return, arguing that he was either unrelated to the mother or the son of one of her sisters.
Jeffreys was able to prove by genetic fingerprinting that the boy was, in fact, the mother's son and he was granted residence.
250 Studies a Week
Cellmark Diagnostics, the British company that first used the test, currently does about 250 such studies a week and has a backlog of 1,500 immigration cases awaiting results, said John W. Huss, vice president of its U.S. subsidiary of the same name.
Genetic fingerprinting has also been used in about 20 criminal cases in Britain, Huss added, with convictions in most.
The most famous case involved the rape-murder of two teen-age girls near the village of Enderby. Police used genetic fingerprinting to exonerate a youth who had been charged with one of the murders and then asked 4,000 local men to voluntarily submit blood samples for testing.
Police arrested a 27-year-old baker, Colin Pitchfork, when he sent a friend, Ian Roy Kelly, 23, to provide samples for him. Pitchfork and Kelly were both charged with obstructing justice in the case, and Pitchfork is awaiting trial for the murders. His blood and semen have been tested, but British authorities will not release the results until the trial.
In Orlando, Fla., genetic fingerprinting was the key piece of evidence in the rape trial of Tommy Lee Andrews, 24. A woman there had been raped in her home by an assailant who covered her head with a cloth so she couldn't see him.
Linked to the Crime
Andrews eventually was linked to the crime because he had been implicated in other rapes carried out in the same manner. His fingerprints were found on a window screen that was removed for entry, but he claimed that he had stumbled over the screen while taking a shortcut through the yard.
Laboratory studies indicated that DNA in his blood was identical to that in semen from the rape victim, and he was convicted in November, said Florida state's attorney Tim Berry.