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News Posted on May 7, 2018

Professor Joh comments on DNA aspect of Golden State Killer case for New Republic

Professor Elizabeth Joh spoke to The New Republic about the use of genealogy website data in the arrest of a suspect in the East Area Rapist/Golden State Killer case.

The FBI and Sacramento County Sheriff’s detectives took suspect Joseph James DeAngelo, of Citrus Heights, into custody April 24. Investigators had matched an old DNA sample from the East Area Rapist/Golden State Killer -the elusive serial rapist and killer who terrorized Californians in the 1970s and 1980s - to a distant relative of DeAngelo’s who had uploaded a DNA sample to a database. Investigators explored that person’s family tree until they pinpointed DeAngelo, then surreptitiously collected a new DNA sample from an item DeAngelo had discarded.

Joh told the New Republic the case underscores Americans’ likely lack of awareness of how new technologies could be used against them. Joh asked: “Do you realize, for example, that when you upload your DNA, you’re potentially becoming a genetic informant on the rest of your family?”

The New Republic story pointed out that the Supreme Court’s forthcoming decision in Carpenter v. United States - which challenges law enforcement’s ability to check a cell phone’s whereabouts without a warrant – likely will set a standard in how to apply Fourth Amendment protections not just for digital data, but also for access to private DNA databases.

Professor Joh’s scholarship focuses on criminal procedure and policing, with a special emphasis on DNA evidence, undercover policing, and new surveillance technologies. She is the recipient of King Hall’s 2017 Distinguished Teaching Award.