Critical genealogist in Golden State Killer case speaks out about her role

OAKLAND, Calif. (KTVU) - A woman given credit by investigators for helping to identify a suspect in the Golden State Killer/East Area Rapist case is now speaking out about her role in tracking down the notorious suspect, a former police officer.

Barbara Rae-Venter, a Northern California attorney who's retired, now works as a genealogist.

A KTVU crew spent a few hours with her Thursday to learn about the technique she uses to help solve cold cases.

"He was on nobody's radar.  Without the DNA, he would have gotten away," said Rae-Venter. 

Her work as a genealogist helping law enforcement led to suspect Joseph DeAngelo of Citrus Heights. He is now facing 13 counts of murder and 13 counts of kidnapping. 

"I was absolutely appalled.  I was trying to remember where I was when he was active," said Rae-Venter. 

She says she was not familiar with the case until last year when she was approached by now retired Contra Costa County District Attorney investigator Paul Holes.  He credits her for helping crack the case.

"We had 8,000 tips over the years and his name was never given to us," said Holes.  

"One of the first things that I do when I start working on a case is I develop a profile of the person I was looking for," said Rae-Venter.  

She says she developed a suspect profile with information from old newspaper articles that suggested the elusive killer may have been in law enforcement or the military.

She then built family trees using information that came from the DNA found in a semen sample recovered from a crime scene that investigator Holes uploaded to GEDmatch, a public website used to help people find relatives.

The GEDmatch search yielded more than 1,000 "genetic cousins."  

Rae-Venter says she was able to develop information that the killer may be prematurely bald and of Italian heritage. 

She says she used the DNA profile to build on family tree information. Eventually, the search was narrowed down to six possible suspects.

"The law enforcement folks called the DMV folks for the six men we had on our list and only one had blue eyes. 

That man was DeAngelo.

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Investigators put him under surveillance and obtained two DNA samples. They tested a straw that DeAngelo threw away and they followed him. 

"He went into a mall to go shopping and when he went inside, they went over and swabbed the handle of his car," said Rae-Venter. 

She says investigators told her the new DNA samples were a match with the initial DNA sample.

"It's a very powerful technique, not just for identifying offenders, but people who are unknown victims," says Rae-Venter.   

She spent her working years as a patent attorney. She got into genealogy after retiring to help people who are adopted find their birth families. 

Now she's in demand to help out with homicide investigations. 

Rae-Venter tells KTVU she's been approached about helping with more than 50 cold cases, homicides and unidentified victims.

She says she plans to help in cases with good, usable DNA. 

She urges people interested in assisting law enforcement with identifying violent criminal offenders and unknown victims of violent crime to do so by doing an autosomal DNA test at any of the major genomics testing companies. When you receive your results, she urges you to upload your raw DNA file to GEDmatch.com.