As the Whorl Turns

Long the Difference Between Guilt and Innocence, Fingerprints Themselves Are on Trial

The case against Robert Hood is far from airtight. The Colorado Springs resident is charged with aggravated robbery and kidnapping; in June, he allegedly forced his victim into a car trunk at gunpoint and drove him around for hours, demanding his ATM password, before abandoning the vehicle at a 7-Eleven. When the victim mentioned that his attacker sported a gold tooth, detectives immediately keyed on Hood, who is also a suspect in a separate murder case.

Besides that lustrous tooth, however, Hood seems like the wrong guy—at least according to his lawyer. The victim said his kidnapper stood 5 feet 11; Hood is barely 5-4. The victim described the attacker's hair as short, dark, and curly; Hood has been bald for years. The victim stated that his tormentor spoke with no discernible accent; Hood speaks with a thick Memphis drawl. According to public defender Deborah Grohs, the victim even fingered someone else. "The day after the man was robbed, he was on the street and he saw the man who robbed him," she says. "The police didn't follow up on it. We found that dude, and he's got a gold tooth! But they arrested Robert anyway."

The weak identification didn't bother the cops one bit. They lifted several partial fingerprints from the vehicle, and a faint palm impression was linked to Hood. That's usually enough to force a plea bargain, since fingerprints have been considered rock-solid forensic evidence for nearly a century.

illustration: Jack Black

But a growing number of legal experts are now questioning whether fingerprints deserve to be a legal slam dunk; they believe that matching crime-scene prints to suspects is more an art than a science, and an imprecise one at that. The skeptics were heartened on January 7, when a court in Philadelphia ruled that fingerprints should not be characterized as scientific evidence. That decision, in the murder-for-hire case U.S. v. Plaza, roiled a forensic discipline once considered beyond reproach, and prosecutors begged Judge Louis Pollak to reconsider. Last week, to the surprise of many, Pollak stepped back from the brink—though he maintains that the science is unproven, he will allow fingerprint experts to offer opinions in his courtroom.

Still, the willingness of so prominent a jurist to seriously question the validity of fingerprints should encourage a fresh wave of challenges. "This is one decision by one trial judge," says Robert Epstein, the public defender in Plaza. "Ultimately, the court of appeals is going to resolve this issue, either in this case or in some other case."

Unfortunately for those who claim to have been wrongfully convicted on the basis of shoddy fingerprints, the present furor won't be a ticket to freedom. Unlike revelations provided by DNA evidence, which can positively verify a convict's innocence, a post-verdict quibble over fingerprints will carry little legal heft. But the uproar has given hope to current defendants like Hood, who formerly stood almost no chance of beating a rap once a fingerprint examiner took the stand. "I've been doing this for 17 years, and every fingerprint case we ever got before, you'd go, 'Fingerprint case? Oh, better plead,' " says Grohs. "We never attacked the reliability of the procedure."

The fingerprint brouhaha has its roots in a 1993 Supreme Court decision, Daubert v. Merrell Dow Pharmaceuticals. For 70 years, scientific testimony had been governed by the so-called Frye standard, which required only that scientific evidence enjoy "general acceptance" to be admissible. Daubert raised the bar significantly, mandating that scientific techniques undergo rigorous testing and peer review. Justice Harry Blackmun, author of the court's opinion, also wrote that a technique should have a "known or potential rate of error . . . and the existence and maintenance of standards controlling the technique's operation."

Given the strictness of those criteria, some legal observers wondered whether fingerprints could pass muster. Despite the widespread acceptance of fingerprints among courts and the public alike—how many Law & Order plots could work without them?—the technique has seldom endured laboratory scrutiny. The methods by which examiners analyze loops and whorls date back to the late 19th century, when phrenology and water cures were the rage, and have changed little since. Simon Cole, author of Suspect Identities: A History of Fingerprinting and Criminal Identification, says that untrained records clerks, not doctors, pioneered the use of fingerprinting for law enforcement purposes; they wantonly added the authoritative-sounding letters FPE to their names, though historians argue over whether the E stood for examiner or expert.

"Just because these guys don't have college degrees or Ph.D.'s, it doesn't mean they don't know what they're talking about," says Cole, who himself holds a Ph.D. in science and technology studies from Cornell. "It could be that it's just an experience-based skill that they've acquired, like an artisanal skill. . . . It's just that you shouldn't call it science."

By the late 1920s, few if any courts doubted that fingerprints qualified as ironclad scientific evidence. In 1930, for example, an Oklahoma court cited a scene in Mark Twain's Pudd'nhead Wilson as proof that fingerprints were a valid tool for criminal identification. Cole maintains that dissent was squelched by an unspoken professional code he calls "the occupational norm of unanimity—the creation of this sense that fingerprint [examination] should not be a profession of dueling experts on the stand. . . . If you made an identification, then the whole rest of the profession should back you up."

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