LOS ANGELES -- The final straw for Christopher Jordan Dorner grew out of a relatively minor arrest outside San Pedro's DoubleTree hotel nearly five years ago.

Dorner and his training officer were called to the well-manicured hotel because a scruffy, angry, mentally ill man would not leave. Together, the Harbor Division officers grappled with the man in a bush until he was shot with a Taser and subdued. But the pair differed in their versions of what happened that morning.

The discrepancy became an obsession for Dorner, who claimed his training officer brutally and unnecessarily kicked the man in the collarbone and face. His intense feelings about that incident are the core of the lengthy, stream-of-consciousness manifesto he wrote to explain why he embarked on a killing spree -- complete with a 40-person hit list.

In the 14-page manifesto written in the parlance of a police report, Dorner directly addresses "America" and describes himself as a heroic figure rendered helpless by a series of racist attacks that began when he was a first-grade student at Norwalk Christian School, when another student called him a racial slur.

The school closed down Thursday during the massive manhunt for Dorner. The disgraced former officer wrote that the first of a series of injustices that defined his life happened at the Norwalk school, where he says he was the only "black kid." He said he was repeatedly disciplined for fighting throughout elementary school, but it was only because he was responding to racist name-calling.

"A fellow student called me a (racial epithet)," he wrote of his first fight. "My response was swift and non-lethal. I struck him fast and hard with a punch an (sic) kick. He then for some unknown reason swatted me for striking (the student). How dare you swat me for standing up for my rights for demanding that I be treated as an equal human being. That day I made a life decision that I will not tolerate racial derogatory terms spoken to me."

Dorner also attended John F. Kennedy High School in La Palma in 1994 and 1995, and went on to graduate from Cypress High School in 1997, according to La Palma Police Chief Eric R. Nunez.

Although Dorner saw himself as a victim with a superior level of integrity, his police supervisors believed he was bullying fellow officers, according to official documents.

After the incident outside the DoubleTree in 2008, Dorner's accusation against his training officer was found to be false. In a series of hearings, hotel bellhops and officers testified that the man taken into custody had not been kicked. Dorner was terminated for falsifying that police report.

The firing fed Dorner's long-festering anger at a society that he describes as racist and brutal in its treatment of him throughout his life. As for his own character, Dorner says "honor, courage, and commitment" are traits embedded in his DNA.

On Sunday, authorities say, Dorner killed the daughter of a former police captain who represented him in a hearing before a disciplinary board as well as her fiance. On Thursday, he killed a Riverside police officer and badly wounded one other, police said.

His violent spree is in direct contradiction to the man who at least one friend called "well-spoken, educated, rational" and who can be seen smiling widely in numerous online photos.

On his Facebook page, Dorner says he is from La Palma, and his manifesto lists a series of cities where he has lived, including Cerritos, Pico Rivera, Thousand Oaks, Yorba Linda as well as towns in Utah, Florida, Nevada and Oklahoma.

He briefly attended California Lutheran University in Thousand Oaks for one semester in fall 1997, university spokeswoman Karin Grennan confirmed.

Southern Utah University spokesman Dean O'Driscoll confirmed Thursday that Dorner attended the university from 1997 to 2001 and graduated with a bachelor's degree in political science and a minor in psychology.

Sports Illustrated's online college football roster archive lists Dorner as a running back there from 1999 to 2000.

James Usera, a Southern Utah University buddy of Dorner's, said the current episode comes as a shock.

"People are looking for predictors, but I just never recognized anything that would indicate he was unstable in any fashion," Usera said.

"He seemed normal, and I know that's not a great descriptor, but that was who he was to me."

Usera said Thursday afternoon that he hadn't read Dorner's manifesto in full but is shocked by what he's heard from reporters.

"It seems very out of character. The individual I knew was a good guy and was upstanding," he said.

Dorner joined the U.S. Navy in 2002, achieving the rank of lieutenant in 2006, according to military records. He served as a reservist in Nevada and San Diego, and was a member of the Coastal Riverine Group deployed to Bahrain from November 2006 to April 2007.

He was stationed at the Navy Mobilization Processing Site in San Diego in 2007 and the Navy Air Station Fallon reserve unit in Nevada in 2009. He left the Navy officially on Feb. 1.

During his service, he was awarded the Iraqi Campaign Medal, National Defense Service Medal, Global War on Terrorism Service Medal, Rifle Marksman Ribbon, Pistol Expert Medal and other commendations.

Long Beach police Sgt. Clint Grimes said Thursday he was stunned when heard Dorner's name on the radio and realized he and Dorner had served in the Navy together.

"I was lying down (at home) and taking a nap and listening to KFI, and that name was like a worm going into my ear," Grimes said. "When they said 'Point Loma,' that's when it hit me. ... I pulled up his picture and that's when I knew it was him for sure."

The two men had overlapping deployments in Kuwait in 2007.

Although they were not close friends, Grimes said he remembered Dorner was excited when he first joined the Los Angeles Police Department and frequently talked to Grimes about his dreams and aspirations as a new police officer.

"I never knew him not to be smiling," he said.

Grimes said Dorner is very bright. Dorner's unit used high-tech sonar equipment to find small boats that could be a threat to naval vessels in port.

"They're not looking for a stupid guy here," Grimes said.

Dorner was also accustomed to military structure, and would insist on following protocol at all times.

"I would say, 'Call me Clint,' and he would say, 'Yes, sir.'"

Dorner graduated from the Los Angeles Police Academy in 2006 and joined the LAPD, but left for a 13-month military deployment that year. He returned to the LAPD in July 2007. That year, his wife filed for divorce, according to court records. The following year, he lost his job.

A Los Angeles police officer who knew Dorner when he was with Harbor Division for a year in 2009 called on him to turn himself in.

"He needs to turn himself in and end this drama," he said.

The officer, who asked that his name not be used, said: "Obviously he's suffering from a mental illness. This is a terrible incident that he's caused."