On the day Christopher Dorner was fired from the Los Angeles Police Department, officials took the unusual step of summoning armed guards to stand watch at his disciplinary hearing downtown.
Those present were nervous that Dorner might do something rash when he learned that he was being stripped of his badge. He was a hulking, muscled man and his body language left no doubt about the anger seething out of him.
"It was clear… that he was wound way too tight," said a police official who attended Dorner's termination hearing and requested anonymity because of safety concerns.
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That day four years ago, authorities now allege, was the start of a free fall into despair and deadly violence for Dorner. Police say the 33-year-old ex-cop killed three people and injured others on a campaign to exact revenge against those he blamed for his downfall.
Friends and acquaintances who knew Dorner before he became a police officer struggled to reconcile the person they remembered with the image of the deeply disturbed man that emerged Thursday from a rambling manifesto that authorities said was published on what they believe is Dorner's Facebook page. The manifesto portrays Dorner as having no choice but to kill in order to reclaim his destroyed reputation.
"I am a man who has lost complete faith in the system, when the system betrayed, slandered and libeled me," the manifesto states.
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Born in New York state, Dorner grew up in Southern California with his mother and at least one sister, according to public records and claims in the manifesto.
Dorner felt isolated growing up as one of the few African American children in the neighborhoods where he lived and was the victim of racism, according to the manifesto. "My first recollection of racism was in the first grade," Dorner allegedly wrote, recalling a fellow student at Norwalk Christian School who called him a racial slur. Dorner said he responded "fast and hard," punching and kicking the student.
It was an early, telling illustration of a notion Dorner returned to repeatedly throughout his life — that he was a victim, often wronged by others, records show.
As a teenager in La Palma, Dorner joined the Police Department's youth program, and decided to pursue a career in law enforcement.
Dorner went on to enroll at Southern Utah University, where he joined the school's football team and was befriended by a teammate, Jamie Usera.
Usera, who grew up in Alaska, said he and Dorner bonded over the feelings of culture shock that came with being outsiders on the predominantly white, Mormon campus.
Usera said he introduced Dorner to hunting and other outdoor sports. "He was a typical guy," he said. "I liked him an awful lot. Nothing about him struck me as violent or irrational in any way. He was opinionated, but always seemed level-headed."
Dorner often brought up race issues and the two had heated, but respectful arguments about the extent of racism in the country, Usera said. "Of all the people I hung out with in college, he is the last guy I would have expected to be in this kind of situation."
Neil Gardner, an assistant athletic director, knew Dorner through football and echoed Usera, saying Dorner was "never a disgruntled guy."
Dorner graduated in 2001 with a degree in political science and, soon after, enlisted in the Navy. Over the next several years, military records indicate Dorner received extensive combat and counter-terrorism training and earned commendations for his marksmanship with rifles and pistols.
In 2005, while still enlisted in the military, Dorner applied to the LAPD and earned a spot in one of the department's training academy classes. An officer in Dorner's class who asked not to be identified because he is not authorized to discuss the case, recalled Dorner as "one of our problem children" who frequently pushed the bounds of authority .
A few days into training, the recruits were explicitly told to only wear white or black shoes for a conditioning run, the officer said. Dorner, however, showed up in bright neon sneakers. "He thought he knew it all, that rules just kind of didn't apply to him," the officer said. "He was not a team player."