Back in 1996, Dunham was booked for felony domestic violence. His wife reported he had choked and hit her in their home. She told officers that Dunham had an alcohol problem and that he often got angry and violent when he drank. The three felony counts were later reduced to misdemeanors.
The I-Team also learned that Dunham worked from 1998 to 2012 as a grounds gardener and construction laborer at Foothill Community College in Los Altos. The vice chancellor for business services there told ABC7 News Dunham resigned from Foothill for retirement purposes.
PHOTOS: San Jose police escort body of fallen officer
Authorities say the fatal shot that came without warning was fired from the balcony of an apartment complex on busy Senter Road. It's the same balcony where the Dunham was found dead.
Police tell ABC7 News that the officer was not alone when he died. They say two other officers rushed to his side as the shooting took place.
"What could he have possibly been going through that would make him do something so abrupt?" asked former neighbor Vaneta Lewis. "How do you go from being a nice person to a killer?"
San Jose police are looking into those questions after Dunham opened fire on officers who came to his apartment unit for a welfare check, resulting in the death of 38-year-old Officer Michael Johnson.
"Officers are obviously crying, grieving, they will do so for quite some time as will many of us in the department," said Officer Albert Morales. "Our hearts, our prayers go out with the family of Michael, our brother."
The shooting happened at around 6:45 p.m. Tuesday. Officers fired back, not knowing if they had hit Dunham. Neighbor Debra Trevaskis lives just two units down. She heard the gunshots and the aftermath.
"Sirens on all sides of the house, and looked down the street, and there must've been 20 police cars blocking off this road," she said.
Using a robotic camera, police found Dunham dead on his balcony nearly nine hours later.
VIDEO: Dispatch audio paints intense picture before SJ officer killed
Those who live at the apartment complex are still trying to make sense of it all.
"It kind of makes you think no one's really safe," said neighbor Alexei Gurtowski. "That's your apartment, there's someone with a gun, it just makes you wonder what really goes down."
They're shocked that one of their neighbors could do something so horrific.
"It just breaks my heart to hear that this happened the way it did happen," said neighbor Billy Lewis.
Those in nearby units are cleaning up after officers used their homes to keep them safe.
On Wednesday night, unlit candles remained on the sidewalk out front as a tribute to an officer taken way too soon.
"All in all, I'm here, the neighbors are here, everyone's safe except for the officer and the gunman," Trevaskis said.
A restaurant that's popular with San Jose police is holding a fundraiser to commemorate the fallen officer and raise money for his family. Brittania Arms will hold the fundraiser on April 2 from 11 a.m. to 2 a.m. at its location at 5027 Almaden Expressway. Manager Steve Moreno tells ABC7 News that all sales -- not profits or a percentage -- will go to the officer's family.
If you would like to extend your condolences to the officer's family and the San Jose Police Department, click here. We've posted a badge on Facebook for you to share, to honor his memory, and his service.
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