He fulfilled his lifelong dream of becoming a Los Angeles police officer in 2005, but saw it unravel three years later when he was fired after a police review board decided he falsely accused his training officer of kicking a mentally ill man in the face and chest. The incident led Dorner to plot violent revenge against those he believed responsible for his downfall, according to a 14-page manifesto police believe he authored because there are details in it only he would know.
Police say Dorner began carrying out that plot last weekend when he killed a woman whose father had represented him as he fought to keep his job. On Thursday - the eighth anniversary of his first day on the job with the LAPD - Dorner ambushed two officers, killing one, authorities said.
Also killed was the woman's fiance, whose body was found along with hers in a parked car near the recently engaged couple's condominium.
"I know most of you who personally know me are in disbelief to hear from media reports that I am suspected of committing such horrendous murders and have taken drastic and shocking actions in the last couple of days," the manifesto reads. "You are saying to yourself that this is completely out of character of the man you knew who always wore a smile wherever he was seen."
David Pighin, a neighbor of Dorner in the Orange County community of La Palma, said the ex-officer kept to himself and left his house and his black Nissan Titan, outfitted with tinted windows and custom rims, impeccably clean.
"There wasn't a scratch on it," Pighin said. "I would see him getting out of his truck and walk straight into the house."
Dorner has no children and court records show his wife filed for divorce in 2007, though there's no evidence one was granted. Pighin believed Dorner lived with his mother and possibly his sister. On Wednesday night, Pighin saw a white van with two armed SWAT officers in front of Dorner's house and later learned about the manhunt.
"We were completely shocked," he said. "This is a good family that appeared to be really nice people. They were really admired in the neighborhood." The 33-year-old Dorner graduated in 2001 from Southern Utah University in Cedar City, Utah, school officials said, where he majored in political science and had an unremarkable career as a reserve running back on the football team.
A friend from those days, Jamie Usera, told the Los Angeles Times that he saw no red flags. The two would have friendly debates about the extent of racism in the U.S. and take trips into the Utah desert to hunt rabbits, Usera told the newspaper.
"He was a typical guy. I liked him an awful lot," said Usera, who's now an attorney in Salem, Ore. "Nothing about him struck me as violent or irrational in any way. He was opinionated, but always seemed level-headed."
In addition to police work, Dorner served in the Naval Reserves, earning a rifle marksman ribbon and pistol expert medal. He served in a naval undersea warfare unit and various aviation training units, according to military records, and took a leave from the LAPD and deployed to Bahrain in 2006 and 2007.
His last day with the Navy was Friday.
"I will utilize every bit of small arms training, demolition, ordinance and survival training I've been given," the manifesto reads. "You have misjudged a sleeping giant."
Police were providing more than 40 protection details for people they determined at high risk after Dorner warned in his manifesto that their families would be harmed.
"I never had the opportunity to have a family of my own. I'm terminating yours," the manifesto says.
In the document, Dorner rails against the hypocrisy of black police commanders who crack down on their white subordinates and catalogues his experiences with racism and injustice, beginning with a schoolyard fight at his Christian elementary school and ending with the disciplinary process that led to his dismissal from the LAPD in 2008.
Dorner recalls that he beat up a fellow student who called him a racial slur on the playground while in the first grade. The principal punished the student, but also chastised Dorner for not turning the other cheek, "as Jesus did."
"That day I made a life decisions that I will not tolerate racial derogatory terms spoken to me," he wrote.
He also recalls sticking up for a fellow cadet in the police academy when other recruits sang Hitler youth songs and taunted the man, who was the son of a Holocaust survivor, and placing another recruit in a choke hold after the man used a racial slur and refused to stop when Dorner objected.
In the latter instance, Dorner filed a complaint against two of his fellow recruits, but only one of the men was disciplined and it left him bitter, according to court records. He would later tell a colleague the LAPD was corroded by the racism of some of its officers.
Dorner graduated and served for only four months in the field before being deployed to the Middle East in 2006 and 2007. When he returned, he was assigned to a training officer, Sgt. Teresa Evans, who became increasingly alarmed at his conduct, according a summary of an interview with Evans in Dorner's disciplinary file.
The burly man with tattoos on his biceps repeatedly asked why he was not sent to reintegration training after his return from war and on one occasion, began weeping in the patrol car and demanded to be taken back to the police academy to be retrained, court documents show.
Dorner also told Evans he was building a house in Las Vegas and intended to sue the department after his probationary period was over - a conversation Evans reported to a superior.
Evans began collecting examples of "deficiencies" in Dorner's police work - including talking to a suspect on a "man with a gun" call without taking cover. After much prodding, Evans recounts, Dorner told her he "might have some issues regarding his deployment."
On Aug. 4, 2007, Evans warned Dorner that she would give him an unsatisfactory rating and request that he be removed from the field unless he improved.
Six days later, Dorner reported to internal affairs that in the course of an arrest Evans had kicked a severely mentally ill man in the chest and left cheek. His report came two weeks after the arrest, police and court records allege.
Three civilian witnesses and a harbor policeman all said they didn't see Evans kick the man, who had a quarter-inch scratch on his cheek consistent with his fall into a bush. The police review board ruled against Dorner, leading to his dismissal.
"The delay in reporting the alleged misconduct, coupled with the witnesses' statements, irreparably destroy Dorner's credibility and bring into question his suitability for continued employment as a police officer," the file reads.
Evans could not be reached for comment. Eric Rose, a spokesman for the Los Angeles Police Protective League, the officers' union, declined to comment on the case or on Dorner.
As a result, he lost everything, including his relationships with his mother, sister and close friends, he wrote in his manifesto.
"Self-preservation is no longer important to me. I do not fear death as I died long ago," he writes. "I was told by my mother that sometimes bad things happen to good people. I refuse to accept that."