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Family DNA Used To Track Down Suspect In ‘North County Creeper’ Case

GUESTS:

Michael Semanchik, staff attorney, California Innocence Project at California Western School of Law in San Diego

Greg Hampikian, , professor of biology and criminal justice, Boise State University

Transcript

Photo credit: 10News

Gilbert Andrew Chavarria is pictured.

For the first time in San Diego County, a suspect has been arrested as a result of a familial DNA investigation.

Gilbert Andrew Chavarria, 27, is in custody in connection with a series of incidents where young girls were molested in their homes during the night.

Police collected DNA samples from some of the crime scenes but that DNA was not in the state or federal DNA databases. Police said what was in the database was the DNA of a close male relative, and by using that, police were able to track down Chavarria.

Greg Hampikian, a professor of biology and criminal justice at Boise State University, said officials found Chavarria through the male chromosome.

"I share 50 percent of my nuclear DNA with my children and 50 percent with each of my parents. It gets quickly diluted after four generations but with males, we can look at the Y chromosome in particular and we can follow that," Hampikian told KPBS Midday Edition on Monday. "In California, they also confirmed with a Y chromosome test — that's a chromosome that's not going to change."

Hampikian said the tool has been used in England since 2003.

"By 2011, they had about 160 investigations and 13 convictions," he said.

The use of familial DNA has been deemed a tool of last resort for investigators in California but even so, some say it raises troubling constitutional and privacy rights issues.

Michael Semanchik, a staff attorney at California Western School of Law in San Diego, said the idea of using DNA to track suspects receives different reactions.

He said civil liberties groups would argue that the DNA database needs to be kept in check, while law enforcement may think it's best to grow it.

"From a privacy standpoint, they have this massive database and they have the ability to get to people who aren't in the database," Semanchik said. "Proponents of familial search say, 'Well, if you don't do anything wrong, you shouldn't care.' But the Fourth Amendment wasn't crafted by the founders to only protect those that are law abiding — it's to protect all citizens."

California does, however, have rigorous standards when it comes to using the database, Semanchik said.

"They can't just use it on every case," Semanchik said. "In order to use this, the investigators have to show that they are out of leads."

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