(CNN) -- What authorities are calling Chris Dorner's campaign of guerrilla warfare against his former comrades in the Los Angeles Police Department has its roots in a hotel lobby in San Pedro, the city's port district. In July 2007, the former Navy officer was an LAPD probationary officer, riding patrol with a veteran of the force, when they were dispatched to check out a report of a disturbance at the DoubleTree Hotel. A man had refused to leave the premises and was sitting on the bench outside the lobby when they arrived. Christopher Gettler had "a glazed look in his eyes," court documents later recounted, and he refused to get up and speak with police. Dorner and his training officer, Teresa Evans, started to take him into custody, but he refused to comply and took a swing at them.
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NEW: LAPD board found Dorner was facing a bad review
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Chris Dorner filed a complaint against his training officer in 2007
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The LAPD cleared the officer and recommended that Dorner be dismissed
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"The attacks will stop when the department states the truth about my innocence," he wrote
In the end, the LAPD cost him not only his police job but his career in the @placeholder, he wrote.