[5] In 1993, almost three years after joining the force in 1990, Liddy was awarded the department's Medal of Valor for actions taken during a shoot-out during the Rodney King riots in 1992, while stationed at the 77th Street Division.

However, the credibility of Perez has been undermined by his testimony in several internal affairs investigations in which three officers, including Liddy, accused of crimes or misconduct were found not guilty or the charges were dropped.

Edward Ortiz and Officer Paul Harper, were the first to be charged with conspiring to obstruct justice by then-Los Angeles District Attorney Gil Garcetti based on Perez's testimony.

The criminal case against the Rampart officers revolved around a 1996 incident in which two reputed gang members were convicted of hitting Harper and Liddy with a pickup truck in an alley.

Afterward, however, Judge Jacqueline Connor vacated the verdicts, saying she had made a “fatal error” in not recognizing that jurors might have misread some "jargon" in the police report that unintentionally lent support to the claim that the officers had lied.

[8] In his lawsuit, Liddy alleged that a disciplinary board criticized internal affairs investigators for giving questionable facts to witnesses with criminal backgrounds who testified against the officers.