Part of ex-cop turned murder suspect Christopher Dorner's rambling manifesto, which touches on everything from his feelings about gay rights to his opinions about the actor Christoph Waltz, delves into the matter that seems to be at the heart of his breakdown. In 2007, Dorner, then a probationary employee with the LAPD, accused his training officer, Teresa Evans, of kicking a schizophrenic man with dementia unnecessarily during the course of the arrest. Dorner omitted the kicks from the arrest report immediately following the incident because he says he was "unsure what to write about the incident on the arrest report, so [Officer] Evans completed the report." But approximately two weeks later, he ended up telling an LAPD captain what he says he witnessed.

At the time of the accusation, the arrested man's father, Richard Gettler, testified that there was merit to Dorner's claims, saying that he asked his son, Christopher, upon returning home "if he had been in a fight because his face was puffy." Christopher "responded that he was kicked twice in the chest by a police officer," according to sworn testimony. Christopher also testified that he was kicked once, but the LAPD Board of Rights decided that his mental illness prevented him from giving an accurate recollection.

Dorner further claimed that after he registered his complaint against Evans, his fellow officers harassed him with schoolyard pranks. This from one of the court documents related to Dorner's case:

Following [Dorner's] complaint about Sergeant Evans, [Dorner] believed someone urinated on his equipment bag at the police station. [Dorner] thought this was in retaliation for his complaint against Sergeant Evans and filed a complaint about this incident. However, an analysis of the unknown substance on [Dorner's] jacket revealed that the substance was not urine.

In the end, the internal LAPD investigation turned into a literal he-said-she-said situation, with no eyewitnesses—aside from Christopher Gettler—able to corroborate Dorner's story. The Board decided to fire Dorner for giving a false testimony, saying that there was not substantial evidence to support his allegations, and pointing out that Dorner had come forward with his complaint only after Evans told him he was danger of receiving an unsatisfactory evaluation. A trial court later rejected Dorner's request for a "writ of administrative mandamus"—a request for a superior court to review an administrative body's ruling—saying that Dorner "failed to carry his burden of establishing that the administrative findings were contrary to the weight of the evidence." Further appeals went nowhere.

In his manifesto, Dorner maintains his innocence, says the LAPD has ruined his relationship with his mother, and claims knowledge of a secret meeting in which Evans' attorney admitted Evans kicked Gettler that night in 2007. "I have attempted all legal court efforts within appeals at the Superior Courts and California Appellate courts," he writes. "This is my last resort. The LAPD has suppressed the truth and it has now lead [sic] to deadly consequences."