If the DNA evidence is irrefutable, DeAngelo may have used his experience in law enforcement to mask his alleged crimes.
DeAngelo was a police officer in the small town of Exeter, near Visalia, from 1973 to 1976. And an officer in Auburn from 1976 until he was let go for alleged shoplifting in 1979.
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"That's surprising that somebody can compartmentalize their lives so well that they can be a police officer and one of the most notorious serial killers of all time," said Keith Komas.
Komas is a co-author of a book about the East Area Rapist case and webmaster of a site that details each of the crimes possibly linked to DeAngelo.
Investigators believe the accused serial killer could be responsible for three South Bay rapes cases --- two in San Jose and one in Fremont.
We could not find anyone in these neighborhoods who were living here 40 years ago, who might remember the impact the crimes had on their sense of safety.
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Police in both cities would not talk about their cold cases.
The crimes occurred in 1978 and 1979, which would coincide with DeAngelo working as an Auburn police officer.
"There seems to be a direct correlation between the rape crimes stopping in Northern California and his dismissal from the police force, both of which happened in July 1979," said book author Komas, "So it's very possible he was using his position or things that he had access to to help facilitate the commission of these crimes."
Inside knowledge of police work may explain how crime patterns shifted from northern to southern California.
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"He'd offend in one area, and he'd move," said Komas. "He'd offend in another area, and he'd move. He took advantage of the lack of communication that existed between police departments and the lack of sharing leads."
Komas pointed out that the statute of limitations has expired for the rape cases but not for homicide.
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Bruce Harrington, whose brother and sister in law were victims of the Golden State killer in 1980, had a message for the sexual assault victims. "Sleep better tonight. He isn't coming through the window."
Click here to read the charging documents for the suspected "Golden State Killer."
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