Familial DNA test leads cops to a killer
WASHINGTON – Lab technicians in North Carolina didn’t have Willard Brown’s DNA on file, but they had his brother’s. And these days, that can be good enough to solve a murder.
Searching for the man who raped and killed a Winston-Salem newspaper editor, the technicians in 2003 compared DNA left at the crime scene with the genetic profiles in the state’s database of convicted felons. The crime scene DNA didn’t match any of the 40,000 felons on file, but it did offer a clue: The unknown man’s profile was remarkably similar to that of one convict, Anthony Dennard Brown. The technicians concluded that Brown and the man they were seeking probably had inherited their DNA - a cellular acid that carries a person’s unique genetic code - from the same parents.
Detectives took it from there. They found Brown’s brother, Willard, scooped up the butts of cigarettes he had smoked and discarded, and got a sample of his DNA from the saliva. It matched the sample from the crime scene perfectly. Last December, Willard Brown pleaded guilty to raping and killing Deborah Sykes in 1984, and was sentenced to life in prison plus 10 years. The DNA testing exonerated Darryl Hunt, who had spent 18 years in prison for the crime and had persuaded a court to order the testing.
The Brown case reflects advances in crime-solving. DNA science, known for its ability to pinpoint suspects’ identities with virtual certainty, is being used to help investigators simply get close to their targets. Investigators in the United States and United Kingdom have begun to solve not just crimes committed by convicts whose DNA profiles are in government databases, but also those committed by relatives whose profiles were not on file. Siblings, parents and even uncles and cousins increasingly are being investigated for crimes because their genetic fingerprints closely resemble the DNA of a known criminal.
Such “familial searches” could expand the power of computer databases authorities in both nations have used for the past decade to compare genetic profiles taken from convicted criminal with DNA left at crime scenes. But the new techniques raise ethical and legal questions: Is it fair for someone who has committed no crime to become a “virtual” suspect because a relative’s DNA is on file? How can familial searches avoid violating the privacy of unrelated people whose genetic profiles happen to resemble that of someone in the databases?
David Lazer, of Harvard University’s Kennedy School of Government, said such familial DNA searches raise the possibility that “if you’re in the genetic neighborhood of someone they’re looking for, the police will be banging on your door.”