Los Angeles (CNN) -- Dr. Conrad Murray, who was Michael Jackson's personal physician, is refusing to testify in the wrongful death lawsuit that the singer's mother filed against concert promoter AEG Live. If called, he will plead the fifth so as not to incriminate himself, the doctor said in a statement sent to the Jackson family. Murray has never been questioned under oath about Jackson's death, which occurred on his watch. He did not testify at his trial, where he was found guilty of causing Jackson's death on June 25, 2009, by administering a deadly overdose of sedatives and the surgical anesthetic propofol in what he told police was an attempt to cure the singer's insomnia.
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Murray: "I will be asserting my Fifth Amendment privilege against self-incrimination"
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Jackson lawyers cancel deposition of Murray
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The Jacksons claim AEG Live bears responsibility for pop icon's death
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AEG: Jacksons canceled deposition because Murray would "destroy" their case
Jackson lawyers, calling it a "smoking gun," argue the e-mail is evidence that AEG Live used @placeholder's fear of losing his $150,000-a-month job as Jackson's personal physician to pressure him to have Jackson ready for rehearsals despite his fragile health.