(CNN) -- Prosecutors filed a motion Monday that could prevent two expert defense witnesses from testifying in the upcoming trial of the doctor accused of fatally drugging pop star Michael Jackson.
Judge Michael Pastor, a California Superior Court judge in Los Angeles County, will now consider the request as it relates to the upcoming trial of Dr. Conrad Murray.
Murray was charged with involuntary manslaughter, after authorities allege that he gave Jackson the propofol that the Los Angeles County coroner ruled caused the singer's death on June 25, 2009.
Prosecutors contend that Dr. Paul White, an anesthesiologist and expert on the drug propofol, and Dr. Joseph Haraszti, a Pasadena-based psychiatrist, should not be able to testify in the trial unless and until Murray takes the stand.
The motion claims that White met and spoke with Murray, after which the anesthesiologist penned a report that included information that the defendant had never given police. Another analysis done by Haraszti also "references new information, apparently obtained from Conrad Murray," prosecutors contend.
Los Angeles County District Attorney Steve Cooley and his deputies claim that it would be unfair to have these experts present analyses that use information from Murray that investigators never received -- unless the primary source of that information, Murray, is first compelled to answer questions.
"This is simply a backdoor attempt to introduce the defendant's new, self-serving statements without being subject to cross-examination," the prosecutors write in Monday's court filing. "Further, such expert opinions are unreliable and lack foundation, since they are based on untested hearsay."
Jury selection in Conrad's trial began last month and will continue into early May. Opening statements and testimony are scheduled to begin May 9.
The defense has argued that Jackson self-administered the propofol in a desperate attempt to get sleep before a rehearsal.
Murray told investigators he was trying to wean Jackson off propofol in the last days of his life, but that he used it in combination with other drugs to help the pop star sleep that last morning.
The defense claims that the singer's dermatologist, Dr. Arnold Klein, injected Jackson with powerful painkillers dozens of times in the last months of his life, unknown to Murray.
The Medical Board of California and Los Angeles County coroner investigated Klein after Jackson's death, but he was never charged, and no action was taken to revoke his medical license.