The Gene Sifters

With brand-new equipment in place, state forensic lab director Terry Laber says he can handle all the DNA police and politicians send his way
Craig Lassig

[Editor's note: A correction ran concerning this story; see end of article.]

In a windowless room on the third floor at the Bureau of Criminal Apprehension (BCA) that used to be home to the departmental copy machine, a portable air conditioner shoots out a concentrated stream of frigid air. Not a bad place to be on a hot summer day, explains Terry Laber--at least not until the two new DNA sequencers are turned on, making the room uncomfortably hot. "We've tried to add ventilation," Laber says as he points to the makeshift tube that connects one of the large, white metal boxes to the ceiling, "But it still gets good and hot in here."

As Laber, assistant director of the BCA's forensic laboratory, points out various pieces of equipment recently purchased with nearly half a million dollars in state and federal funds, three forensic scientists traipse about the space, carefully avoiding collisions as they move trays of test tubes from one countertop to the other. Those tubes contain the processed blood of sex offenders--samples the state has collected from offenders convicted of felony sexual assault since 1990. They are about to be fed into the new machines, which will examine the genetic material found in the blood and decode its unique patterns with a laser beam. The result--a set of 26 digits often referred to as a "genetic fingerprint"--will be stored on the hard drive of the Macintosh computer sitting between the two machines.

The principle of DNA sequencing isn't new. But the speed with which the new machines can process samples, Laber says, represents a quantum leap for the lab's capability--a leap that, this spring, prompted the state legislature to drastically expand the number of offenders whose DNA will be entered into the database. Under a measure scheduled to take effect next summer, the state will process DNA not just from sex offenders, but from people convicted of crimes such as murder, manslaughter, assault, robbery, kidnapping, burglary, and indecent exposure. "We're taking a very proactive stance," says the bill's author, Rep. Doug Fuller (R-Bemidji). "These are serious criminals who aren't just committing a single crime."

In fact, felons must commit more than one offense for the database to work. When Laber's staffers receive genetic material from a crime scene, they compare its "fingerprint" to those they already have in the computer. If there's a match, police can make an arrest even if the repeat offender was not a suspect before--an event the BCA refers to as a "cold hit." The database can also eliminate potential suspects from an investigation: If, say, a previously convicted sex offender's DNA does not match the evidence found at a new crime scene, that person will be ruled out as a suspect, since the odds of one individual's DNA matching another's are extremely low. "Instead of making up some number like 'one in kajillion,'" he says, "we usually tell the press the odds are about one in a billion. But the actual odds are almost zero." (In mathematical terms, those odds are, on average, one in 1023--a 1 with 23 zeros behind it.)

Right now the state's database contains DNA "profiles" of about 10,000 sex offenders--just about right, Laber explains, since with the old equipment his staff was able to process only about 1,000 samples each year. With the new machines, it will take but a month for the same staff to add the 4,000 samples expected to start rolling in each year once Fuller's law takes effect next summer. "You take what's going on in Waseca right now," the state representative says, referring to the investigation of the murder of 12-year-old Cally Jo Larson this April. "If we currently had the database that we'll have in two years, this case may very well have been solved by now."

The database expansion continues Minnesota's tradition of staying on the forefront of forensic DNA technologies. In 1991, a year after Minnesota became one of the first states to establish a DNA database, the BCA linked Martin Perez--whose genetic fingerprint was on file because of a rape conviction earlier that year--to the rape and murder of Lowry Hill resident Jean Broderick. Perez became the first person in the United States to be arrested and brought to trial based on DNA evidence.

Minnesota was also one of seven "flagship" states that worked with the FBI to create a national DNA database, called the Combined DNA Information System (CODIS), in 1993. In 1997 Wisconsin authorities, who did not have the capabilities to analyze DNA evidence, asked the Minnesota BCA to process a sample obtained during an investigation. The sample matched the DNA of a sex offender registered in Illinois, and Minnesota became the first state to score a "cold hit" on the national system.  

"We've had about 20 cold hits," Laber notes as he leafs through the file that serves as a BCA trophy case; once the new database gets up and running, he adds, that number should increase dramatically. In addition to processing samples faster, the new DNA sequencers use a new technique called Polymerase Chain Reaction (PCR), which "amplifies," or clones, a piece of DNA millions of times. So while the current database requires that the evidence taken from a crime scene, such as a semen stain, be about the size of a dime, the new database works with cellular material about one-hundredth that size.

PCR also allows the DNA sequencers to work with old, almost mummified samples. In June, for example, the technology led to the arrest of a Connecticut man after police in that state obtained DNA evidence from a corpse 26 years after the murder took place. The Minnesota BCA has already used PCR to solve several cases where the only evidence found at the crime scene was the dusting of lip cells on a cigarette butt. "About 50 percent of the samples we currently receive cannot be run against the [current] database," Laber says. "So when you combine twice as many samples against the 3,000 extra profiles added [to the new database] yearly, you're going to get a lot more hits."

Numbers like these have gotten politicians and law-enforcement officials thinking. Four states--Virginia, Wyoming, New Mexico, and Alabama--now require all convicted felons to provide samples, and Louisiana recently passed legislation allowing police to take blood from anyone they arrest, much the way they now collect fingerprints. New York City Police Commissioner Howard Safir drew headlines last winter when he called for a system like Louisiana's--only to be upstaged by Mayor Rudolph Giuliani, who said he would consider taking DNA samples from every newborn in the city. In response, the American Civil Liberties Union (ACLU) accused New York politicians of trying to create a "brave new world."

The Minnesota branch of the ACLU has been watching the state's database expansion and plans to develop an official stance by this fall. The group's legal counsel Teresa Nelson says the MCLU is worried that taking blood samples from all felons may violate the Constitution's protection against unreasonable search and seizure. In addition, she says, there are concerns about how the database could be used in the future. "Just because the government says that they are using this in a limited sense doesn't mean that's how it'll be down the line," Nelson explains. "If employers were able to get this information, maybe they would stop hiring people with a certain genetic disposition." So far, claims Nelson, there is no legal prohibition against outsiders accessing the DNA information through the Minnesota Data Practices Act, which governs the public's access to government data.

Don Gemberling, the director of the state's Information and Policy Division, says Minnesota does have statutes preventing DNA information from being released. What the state lacks, he says, are data-protection laws of the sort many European countries have on the books--laws that prevent governments from using personal data for reasons other than those for which the information was originally collected.

"Have you ever seen Gattaca?" Gemberling asks, referring to the 1997 film set in a society where social standing was determined by DNA profiling. "This database can't be seen in a vacuum, but rather in the larger context of the human genome mapping project." (The project is an international scientific collaboration determined to map out the entire genetic blueprint of the human species.) Without data-protection laws, Gemberling argues, DNA databases might be used to hand down tougher sentences for people considered to have a genetic disposition toward violence, or to prevent them from receiving social services.

Laber dismisses such arguments with an air of annoyance, saying they arise from a misunderstanding of the science involved. Since most people are physically very similar, he explains, the sections of DNA that control physical attributes aren't different enough to be used as a fingerprint. His database focuses on segments that don't seem to have any purpose, because they vary most strongly from one person to the next. "We're only storing junk DNA," he says. "That's why it works in the first place." (The BCA does, however, keep part of all blood samples on file, in case the processing technology changes yet again.)

If anything, Laber argues, civil libertarians should be welcoming a technology that in any given case can eliminate approximately 15 percent of the people police deem "extremely good suspects." Witness the 1994 conviction of serial rapist Timothy Baugh. "In that case you had an innocent man being positively identified out of a police lineup," Laber says; that man was later cleared by DNA evidence. "Sometimes eyewitnesses aren't so great."  

But for Fuller, the state representative, the emphasis isn't so much on protecting the innocent as on finding the guilty. "Let me be clear about this," he says. "It's all about catching the bad guys. And the more people we have on file, the more bad guys we're going to catch." Fuller says he may soon consider drafting legislation that would require people convicted of gross-misdemeanor offenses that are violent or sexual in nature (such as fifth-degree sexual assault, or unauthorized fondling) to give DNA samples. And Laber says his lab may soon be ready for that: "We're taking it step by step," he explains. "If we can get the 10,000 [samples] transferred over from the old database and can handle the 4,000 cases that will be coming in, then we hope to step it up another level next March."

Correction published 7/20/1999:
Because of a reporting error, "The Gene Shifters" incorrectly attributed the authorship of the new state law mandating expanded processing of convicted felons' DNA. The state representative who authored the bill and who was quoted in the story is Doug Fuller. The above version of the story reflects the corrected text. City Pages regrets the error.

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