Joseph James DeAngelo, 72, was arrested Tuesday after investigators matched crime-scene DNA with
genetic material stored by a distant relative on an online site. From there, they narrowed it down to the Sacramento-area grandfather using DNA obtained from material he had discarded, Sacramento County District Attorney Anne Marie Schubert said.
Civil libertarians said the practice raises troubling legal and privacy concerns for the millions of people who submit their DNA to such sites to discover their heritage.
There are not strong privacy laws to keep police from trolling ancestry site databases, said Steve Mercer, the chief attorney for the forensic division of the Maryland Office of the Public Defender.
"People who submit DNA for ancestors testing are unwittingly becoming genetic informants on their innocent family," Mercer said, adding that they "have fewer privacy protections than convicted offenders whose DNA is contained in regulated databanks."
GEDMatch is a free site where users who have DNA profiles from commercial companies such as Ancestry.com and 23andMe can upload them to expand their search for relatives.
Holes said officials did not need a court order to access GEDMatch's database of genetic blueprints.