In 1981, Pardo was one of four Sweetwater officers charged with brutality, but the cases were dismissed.
He was fired four years later after he flew to the Bahamas to testify at the trial of a Sweetwater colleague who was accused of drug smuggling. Pardo lied, telling the court they were international undercover agents.
Then over a 92-day period in early 1986, Pardo committed a series of robberies, killing six men and three women. He took photos of the victims and recounted some details in his diary, which was found along with newspaper clippings about the murders. Pardo was linked to the killings after using credit cards stolen from the victims.
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