ALAMO (CBS SF) -- An investigation into the shooting death of a California Highway Patrol officer on Interstate Highway 680 near Alamo last September found that the shooter was mentally troubled and pro-guns.
The Contra Costa County Sheriff's Office report released Thursday comes after CHP Officer Kenyon Youngstrom, 37, was shot and fatally injured after pulling over a driver with an obstructed license plate on southbound I-680 on the morning of Sept. 4.
The shooter, Christopher Boone Lacy, was shot by a fellow CHP officer who arrived at the scene.
Both Youngstrom and Lacy were later pronounced dead at John Muir Medical Center in Walnut Creek.
In the months since the roadside shooting, authorities investigated Lacy's motive and background, interviewing as many as 100 family, friends, neighbors and co-workers.
Investigators analyzed data from Lacy's computers and other digital devices.
The investigation revealed that Lacy had suffered a mental breakdown in 1997 while he was in college. He was diagnosed with bipolar disorder.
Police found a handwritten suicide note at his home that is believed to have been written during his college breakdown.
He earned his master's degree in computer science from San Francisco State University in 2005.
A year before the shooting, family members told authorities that Lacy had become a "loner," and moved to Corning, California, where he lived in a trailer.
He worked temporary jobs in Silicon Valley where he had a rented room in Sunnyvale.
Six of his computers revealed that Lacy had a lot of literature about libertarianism and the Sovereign Citizen Movement, and that he was a fervent supporter of the second amendment.
Also on his computers, Lacy had a "wish-list" that included "solar panel, water filter, sleeping bag, pond fence, bulletproof vests."
He had also visited a website about creating explosives.
The gun used to fatally wound Youngstrom was registered to Lacy and lawfully purchased in 2010. He did not have a concealed weapons permit.
His Jeep Wrangler that he was pulled over in was registered in his name.
The report concluded that there was no indication that Lacy intended to kill or assault law enforcement officials, although he strongly identified as a Sovereign Citizen and rejected the idea of government and laws.
Lacy's previous contact with police included an arrest for suspected drunken driving on a motorcycle in Sausalito in 2006.
In that incident he behaved strangely, refusing to speak and handing the officer a "Bill of Rights" card.
The investigation was conducted by agencies including the sheriff's office, the CHP, and Contra Costa County District Attorney's Office.
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