The whole world knows about the extraordinary reduction in crime that New York City has won in recent years by applying a host of innovative new crime-fighting techniques, from computerized crime tracking to quality-of-life policing. But there's a cutting-edge way to slash Gotham's crime rate by another 15 percent: using DNA evidence left behind by criminals to situate them at the scene of the crime. In England, police have pushed DNA profiling to the forefront of crime fighting, helping to solve tens of thousands of crimes. But here in the United States, efforts to expand DNA testing are lagging, in part because of the relentless, if ill-founded, opposition of the American Civil Liberties Union. It's a shame, because not only does the use of DNA testing in law enforcement promise to put more of the guilty behind bars; it has also worked to free innocent people imprisoned for crimes they didn't commit.

The inventor of DNA testing—he gets a small royalty every time investigators use the process—is geneticist Alec Jeffreys of Leicester University in England. In the early 1980s, as Jeffreys experimented with extracting DNA from human muscle tissue, he made a remarkable discovery. (Deoxyribonucleic acid, or DNA, of course, is the double-helix configuration of protein molecules in cells that determines the inherited genetic characteristics of all living things.) Certain seemingly purposeless segments of human DNA, Jeffreys realized, were in fact "genetic markers," as unmistakably unique to each individual (with the exception of identical twins) as a fingerprint. The genetic markers show up in the nucleus of human cells from blood, bone, hair follicles, saliva, semen, skin, sweat, and other bodily excretions. They're the same from cell to cell and remain so throughout an individual's life.

Recognizing the potential benefits to solving paternity suits and to law enforcement of his discovery, Jeffreys found a way to process these markers, using electricity and radioactive labelling, so that they form a distinct bar-code-like pattern on X-ray film. Police could now match the bar codes from DNA evidence at a crime scene with DNA samples taken from suspects—a surefire way to prove that a suspect committed the crime or, at the very least, was at a crime scene. Jeffreys appropriately called his technique "DNA fingerprinting."

Jeffreys's pathbreaking work helped crack one of England's most infamous crimes, the brutal 1983 rape and murder of a 15-year-old girl as she walked home along a country lane in the tiny Leicestershire village of Narborough. Frustrated investigators found no suspects. Three years later, though, another young girl turned up dead in Narborough, sexually assaulted and murdered in the same grisly manner. This time, police arrested 17-year-old Rodney Buckland, a worker in a local mental hospital, who made statements incriminating himself in the new murder but proclaimed his innocence in the earlier slaying. The cops, certain that Buckland had raped and killed both girls, sent semen samples from the two attacks, along with a blood sample from the suspect, to Leicester University for Jeffreys to examine with his new method.

Jeffreys's DNA analysis—at that time it was a process of several hundred steps that took weeks to complete—turned out to be great news for Buckland. While the DNA evidence confirmed that the same offender had committed both crimes, it also showed that Buckland couldn't have been the perpetrator. His incriminating statements were false. As Jeffreys later recalled, "[Buckland] was the first man ever proved innocent by molecular genetics, and without the evidence he would have gone to jail for the rest of his life."

British police then began a massive manhunt for the real killer, using Jeffreys's new technology. To find DNA matching the forensic evidence from the crime scene, they took blood samples from every male aged 13 to 30 in the vicinity of Narborough—over 5,000 men in all—and sent them to a forensic laboratory for testing. At first, they found no match. But when a townsman in a pub overheard 27-year-old Colin Pitchfork drunkenly telling friends that he had persuaded a buddy to give a DNA sample in his stead, the cops had their killer. A DNA profile confirmed that Pitchfork had raped and murdered the two girls, and he received two life terms.

Since Jeffreys's DNA fingerprinting brought Pitchfork to justice, the process has become much easier to do. With today's advanced technology, DNA testing takes not weeks but hours. Lab technicians can use even minute quantities of DNA to create a genetic marker by tagging the person-identifying DNA segments with a chemical "primer" and copying them over and over until they have created a sufficiently large test sample. Investigators can now retrieve a suspect's DNA from a small drop of blood left behind on a broken window at a burglary scene, or from the slightest residue of a criminal's sneeze, or, as President Clinton discovered, from a months-old dried stain on a dress. The margin of error for a complete match is so small as to be irrelevant.

DNA technology is advancing fast. The latest breakthrough allows testing of "mitochondrial DNA"—genetic material outside the cell's nucleus—and it can get a match even from a severely degraded sample. In the future, cops will doubtless have high-tech portable labs that will analyze a DNA sample at the crime scene itself. Predicts Chris Hadkiss, the DNA manager for the Forensic Science Service in London, an independent lab that tests DNA for police: "It will not be long before police officers will be able to scan DNA evidence at a scene as easily as they check number plates." "I call it the fingerprint of the millennium," Sergeant Ray Rawlins, who coordinates DNA collection at San Diego County jails, tells the San Diego Union-Tribune. "It's going to solve a lot more crimes." And, provided that the proper technology and trained personnel are in place, it's affordable too: an individual DNA test costs just $50 to $100 to perform. The potential savings to society are huge: shorter investigations and trials, and a deterrence factor that will significantly reduce crime, as potential criminals realize that even their own sweat can incriminate them.

In the United States, police have used DNA to solve a number of violent crimes that otherwise would have gone unpunished. Investigators' first U.S. success with DNA testing came in 1987, when it led to the conviction of Tommy Lee Andrews for serial rapes in the Orlando, Florida, area. "Without the DNA, I don't think we could have gone to trial," the Orange County assistant state's attorney remarked at the time.

These days, similar stories fill the news. Take just three notable cases. In 1998, St. Petersburg, Florida, police used DNA to nab the notorious "Duck Robber"—his victims all described his duck-like waddle—wanted for a series of robberies and two rapes. Police believed that Charles Peterson was the perpetrator, in part because of his markedly toes-out gait, but they couldn't link him to any of the crimes. Though the cops had DNA evidence from the rapes, Peterson refused to supply them with a DNA sample for comparison. So the police got a sample another way. Trailing Peterson in an unmarked car as he drove his motorcycle around town, an officer saw him lean over and spit while stopped at a traffic light. The officer quickly pulled over and scooped up the spit with a paper towel. Lab analysis showed that the DNA from Peterson's saliva matched that of the forensic evidence. Cops had all they needed to cook the Duck Robber's goose.

In a second exemplary case, DNA identification proved superior to eyewitness identification. In the mid-1990s, a rape victim, certain that she had seen her attacker on the street, notified Indiana police, who arrested Robert Flowers as a suspect. But Flowers claimed that he was innocent, and DNA analysis proved him right. The victim was so sure that her identification was correct, however, that police asked whether Flowers had any siblings with a similar appearance. He did, and a DNA fingerprint showed Flowers's brother to be the rapist.

In 1998, in a third widely publicized case, a 12-year-old Phoenix girl convinced police that her grandfather had been sexually abusing her. After watching an NYPD Blue episode in which a rape victim saved the semen her attacker had left behind, the young girl, using a cotton swab on herself, gathered sufficient DNA evidence to have her grandfather arrested.

DNA fingerprinting can do more than identify criminals: just as important, it can exonerate the innocent. Nationally, it has freed more than 60 wrongly imprisoned individuals. All had exhausted their appeals and had their post-conviction motions denied, so without the recent advances in DNA analysis they would have had nowhere to turn.

The most famous of these cases is that of Marine Corporal Kevin Green, imprisoned for nearly 16 years for the 1980 attempted murder and sexual assault of his pregnant wife and the killing of their unborn child. At the Los Angeles-area crime scene, Green told investigators that he had gone out to get a hamburger, leaving his wife home in bed. Returning 40 minutes later, he claimed, he found his wife beaten unconscious and near death. Though cops at the scene found the hamburger still warm, they arrested him—ignoring the similarity of the attack to those of the "Bedroom Basher" then terrorizing L.A. by breaking into houses and raping and murdering women. Green's wife, regaining consciousness in the hospital, said that her last, fuzzy memory before the attack was of her husband holding a blunt object. It was enough to convict him.

But Green maintained his innocence. "The only thing I had left to give my daughter is the truth, and stand up for the fact that she did not die by her father's hand," he recently recalled. In 1996, DNA evidence proved that the semen from the sexual assault wasn't Green's. Later, an inmate at California's Avenal State Prison, Gerald Parker, confessed to the crime after DNA linked him to it. Parker also admitted to being the Bedroom Basher. He was weeks away from release at the time.

So crucial is DNA becoming as a defense tool that Yeshiva University's Benjamin N. Cardozo School of Law in New York has launched the "Innocence Project," led by lawyer Barry Scheck, to examine DNA evidence in cases in which prisoners continue to claim their innocence. Terry Leon Chalmers owes his freedom to it. In 1986, a court in suburban New York had sentenced Chalmers to 12 to 24 years for rape. The victim had identified Chalmers in a police photo and then picked him out in two subsequent police lineups. At trial, Chalmers offered an alibi defense but couldn't corroborate it. In the summer of 1994, after eight years in prison, Chalmers, with the help of the project, had his blood sample taken and its DNA compared with that of forensic evidence preserved from the original crime scene. The DNA analysis proved Chalmers's innocence; soon after he was a free man. To date, the Innocence Project has won the post-conviction release of 38 innocent defendants, eight of them from Death Row.

England, where DNA testing is now a key police tool, has developed an exemplary national DNA identification network. In it, police take a suspect's genetic fingerprint at arrest for any felony or misdemeanor, simply by brushing a cotton swab against the inside of his cheek—there's no longer any need to draw blood to get a DNA sample. The cops then send the sample to the independent Forensic Science Service, a laboratory that contracts with local police agencies throughout the United Kingdom to analyze DNA and other forensic evidence.

Since April 1995, the British have gathered DNA profiles of more than 500,000 criminals—the number grows weekly—and police have linked 70,000 suspects to crimes through their DNA. Even if cops haven't identified a suspect, DNA testing has linked together more than 8,200 crime scenes, so that investigators realize early on that they're after the same perpetrator for more than one crime. As the database of known offenders increases, the rate of matches will increase too. Observes British prime minister Tony Blair, an enthusiastic supporter of DNA use in law enforcement: "More testing will help solve more crimes and catch more criminals and not just for murders and sexual offenses. It will help in our fight to cut the crimes which affect most people, like burglary and car crime."

What Blair says is true. Though U.K. law enforcement has used DNA primarily to solve violent crime, DNA profiling has yielded unexpected benefits in combating burglary and auto theft, too—crimes that in England, as in the U.S., police rarely solve. A burglar, after all, might leave hair follicles or scraped-off skin at the crime scene, or a car thief might leave sweat on the steering wheel of a stolen car, giving police all the DNA evidence they need. Of the 70,000 cases that DNA has helped clear in the U.K., roughly half were burglaries, and another 10,000 were car thefts.

U.S. law enforcement lags in taking advantage of DNA testing. To date, the nation has solved only 1,000 or so crimes with the new technique. Many states don't have laws that let crime fighters routinely profile suspects' DNA. Here in New York, for example, though the State Legislature has expanded cops' power to take DNA samples, it still limits the procedure to defendants convicted of a narrow set of violent crimes. Since arrest records show that violent offenders usually commit minor crimes, too, routinely testing minor offenders will almost certainly catch major felons, just as ID checks on quality-of-life offenders have turned up criminals with outstanding felony warrants. Moreover, though most states have started to collect DNA samples, either they haven't profiled many of the samples yet, or they've profiled them in a way that's incompatible with the latest technology. Most cops lack training in the use of DNA. As Barry Scheck has put it, "Frankly, we have a national scandal in the failure of government to fund crime labs and train law enforcement to take advantage of DNA technology as an investigative tool that can both exonerate the innocent and find the guilty."

Nor has the federal government woken up to DNA's anti-crime importance. The feds, like New York, have limited investigators to taking DNA samples from convicts, rather than from all arrestees. Drawing on state databases, the FBI is building its DNA library, the Combined DNA Index System (CODIS), to serve as a national database, but it has a huge backlog of some 500,000 unanalyzed test samples, and it can't match samples tested with the old technology with those done with the newer methods.

A major reason DNA fingerprinting remains stalled in the U.S. is the opposition of civil libertarians. They claim that collecting DNA data is "Orwellian," or—mixing dystopias—that it heralds a nightmarish "Brave New World," as ACLU associate director Barry Steinhardt ominously puts it. When Maryland law enforcement officials proposed taking genetic profiles of all the state's violent felons, an ACLU rep warned, "I don't think anyone should ever be comfortable that the government is collecting a database of personal information." The ACLU has launched court challenges to DNA data banks in California, Massachusetts, and other states. The U.S. Supreme Court has yet to address the constitutionality of DNA data banks.

But of course police already keep a data bank of personal information—criminals' fingerprints. DNA analysis is merely a more sophisticated fingerprint—though the ACLU disagrees. "Fingerprints are two-dimensional representations of the physical attributes of our fingertips . . . useful only as a form of identification," Steinhardt says. "DNA harbors our innermost secrets. There are markers for everything for up to 400 diseases, genes for violent tendencies. . . . There may be a gay gene." DNA collection, civil libertarians argue, could lead to genetic discrimination if, say, insurance firms get their hands on the original samples from which police have drawn their genetic markers. But the genetic markers themselves, though important to police, are "junk" DNA that offer no information about an individual's predisposition to disease. Lawmakers could easily require that the original DNA samples be destroyed after lawmen have extracted their identifying bar codes from them, making impossible any future discriminatory use.

Civil libertarians also fear that taking DNA samples from arrestees means that DNA evidence will still be at law enforcement's disposal even if a suspect has been exonerated, violating the presumption of innocence at the heart of the American legal system. But just as the law requires a suspect's fingerprint records destroyed if a court finds him innocent, so it can require the destruction of DNA records of the innocent. And finally, civil libertarians argue that taking DNA from unwilling prisoners violates the Fourth Amendment's prohibition of unreasonable searches and seizures. In a case decided by the Massachusetts Supreme Court last April, the ACLU argued that taking blood from the state's violent convicts to set up a DNA database, as Massachusetts was doing, was unnecessarily invasive—especially because investigators were taking the samples against the convicts' will. The high court disagreed and found that the governmental interest in a "particularly reliable form of identification outweighs the minimal invasion of a pinprick." Using a cotton swab to collect the DNA sample, as English investigators do, wouldn't be intrusive at all.

Despite civil libertarians' ceaseless efforts, DNA analysis has begun to gain support in America among ordinary citizens. Carol Sievers is one passionate supporter. In 1994, someone broke into the Virginia home of her 24-year-old daughter, Hope Denise Hall, and raped and murdered her. The killer slashed Hall's throat and stabbed her so fiercely that he bent the knives he used. Police originally suspected a frustrated suitor, but the DNA evidence proved him innocent.

For two years, police unsuccessfully tried to solve the case using standard law enforcement procedures, until one day, on a whim, a forensic scientist at the Virginia State Laboratory ran DNA data from the crime scene through the FBI's CODIS database. CODIS quickly returned a "cold hit"—an exact DNA match—identifying the killer as Shermaine Ali Johnson, doing time in a Virginia prison for two rapes he committed at around the same time as the Hall murder. Based primarily on the DNA evidence, a court sentenced Johnson to death for the rape and murder of Hall. "We thank God for DNA and the technology," Sievers said. "We want to make sure that the right people are in prison."

Other Americans might remain skeptical about the effectiveness of DNA testing after the infamous O. J. Simpson trial. But the prosecution's failure to convict Simpson had nothing to do with the failure of DNA identification as a science. Though investigators found Simpson's DNA at the murder scene, the sloppiness of the investigation hampered efforts to establish a logical sequence of events that would have proven him guilty beyond doubt. Investigators moved the bodies of Nicole Simpson and Ron Goldman; detectives used their bare hands to gather evidence at the murder scene; scientific experts spilled blood onto evidence at the lab. Such procedures don't support a science as painstaking as DNA testing.

The federal National Institute for Justice has designed appropriately exacting procedures for gathering and processing DNA evidence. Every time an investigator retrieves an item at a crime scene, the Institute recommends, he should don a fresh pair of sterile latex gloves—the only way to prevent possible contamination of evidence. There's no question that DNA analysis will require a higher level of professionalism from police departments. The procedures for opening evidence at the lab should be just as strict.

The U.K. has proved that, with a solid commitment to building a national database, DNA profiling can quickly become a revolutionary new tool of law enforcement. It took less than a year to get England's national DNA identification network up and running. To catch up, the U.S. needs to jump several key hurdles.

First, state legislatures across the country—New York's included—must authorize police and other law enforcement officials to take DNA samples from every person arrested, preferably with the simple and painless cotton-swab method the U.K. uses. Second, state legislatures should provide sufficient funding to allow for the analysis of the large backlog of untested samples that many states have accumulated; the federal government should ensure that its own backlog gets cleared up too. Third, federal and state laws should mandate that all persons presently incarcerated in state or federal prisons, or in local jails, as well as all parolees and probationers, should have DNA samples taken.

Fourth, Congress should authorize the establishment of a new, state-of-the-art federal DNA database that receives and stores all this DNA information. Alternatively, the FBI could clear up the CODIS backlog and bring the system up to speed by including the DNA of all those arrested, already convicted, and paroled. Since most criminals ply their trades across state lines, state police officials need to have access to a comprehensive national DNA database. New York police should have on hand the available data for Newark criminals, say, and Pennsylvania cops should be able to access data on New Jersey's worst offenders. Fifth, police departments throughout the country must adopt proper crime-scene protocols.

Finally, it is crucial that America have an independent and highly professional laboratory system, like England's Forensic Science Service, to process all forensic DNA samples. Local police departments throughout the U.S., along with federal law enforcement agencies, would contract with the lab for processing at regional centers. Since the lab would be independent, there would be no inherent bias among technicians and other scientific personnel to promote convictions. Further, defense attorneys and others could contract with the independent service to have their own scientific tests completed. An independent lab ensures a neutral process with one agenda—establishing the truth.

In 1902, New York's police commissioner sent an aide to London to learn about the new English system for identifying perpetrators. Called fingerprinting, the ink-based process revolutionized the collection of crime data. As we begin the new millennium, it's clear that England is once again leading the way in forensic science. It's time to catch up.


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