Some were stunned to learn that the Joseph James DeAngelo Jr. ,who was arrested for being the Golden State Killer, once worked as a police officer. I wasn't because of a chilling encounter I experienced years ago.
Sacramento County Sheriff
Some were stunned to learn that the Joseph James DeAngelo Jr. ,who was arrested for being the Golden State Killer, once worked as a police officer. I wasn't because of a chilling encounter I experienced years ago.
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Programming note: For more on the Golden State Killer case, watch HLN’s marathon of “Unmasking a Killer” starting at 12 p.m. ET on Saturday, April 28, or binge the series now on CNNgo.

(CNN) —  

When police announced they had finally caught the Golden State Killer, Bruce Harrington had a simple message for the politicians who fought his tireless efforts to expand California’s criminal offender DNA database.

“You were wrong,” he said.

Harrington, whose brother and sister-in-law were killed in 1980, spent years in front of public safety committees, pleading with them to embrace DNA technology.

“And frankly I ran into a buzz saw of opposition.”

Many state elected officials and rights groups fiercely opposed any attempt by the state to expand its DNA collection database.

Critics cited the privacy rights of people in police custody and questioned the constitutionality of allowing the state to gather DNA samples without evidence of guilt.

Bruce Harrington, whose brother Keith Harrington and his wife, Patty, were viticms of the Golden State Killer
Sacramento Bee/TNS/Getty Images
Bruce Harrington, whose brother Keith Harrington and his wife, Patty, were viticms of the Golden State Killer

What the DNA database law does

In 2004, California voters passed Proposition 69, known as the “DNA Fingerprint, Unsolved Crime and Innocence Protection Act.”

It gave the state broader powers to collect DNA. Now, it could get samples from anyone not just convicted of a felony, but even arrested for one.

In some cases, authorities could also collect DNA from misdemeanor arrests.

DNA’s role in the capture

This week, when officials arrested the man believed to be the Golden State Killer, they said the break came from a DNA sample.

They didn’t elaborate exactly how DNA helped them identify former policeman Joseph James DeAngelo as their suspect in a string of murders and rapes during the mid-1970s and 1980s.

A view of the home of accused rapist and killer Joseph James DeAngelo in Citrus Heights.
Justin Sullivan/Getty Images
A view of the home of accused rapist and killer Joseph James DeAngelo in Citrus Heights.

But outside the forensic lab where authorities announced the arrest, Harrington recounted his efforts to reporters.

“I began my quest in the mid-’90s when DNA finally came of force into the world of forensic science,” he said.

DeAngelo was charged this week with capital murder in the 1978 killing of Katie and Brian Maggiore. The 72-year-old man described by neighbors as a recluse is believed to have carried out 12 killings and at least 50 rapes in California, authorities said.

Those crimes included the deaths of Harrington’s brother Keith and sister-in-law Patrice, who were beaten to death in August 1980. Patrice Harrington was also sexually assaulted.

“That case was a strong incentive to work on developing the California state database, which now has about 2 million profiles,” Orange County District Attorney Tony Rackauckas said.

“All the time, we had this case in mind – eventually hoping to solve this case.”