LOS ANGELES - California Attorney General Jerry Brown is opening an independent investigation of several doctors whose names have come up in connection with the probe into pop star Michael Jackson's death.
Brown said in a statement Friday that his investigation comes at the request of the Los Angeles Police Department.
The statement said that on Aug. 20 police met with representatives of the attorney general's Bureau of Narcotice Enforcement and the Drug Enforcement Administration to discuss information uncovered in the Jackson death investigation. Bureau agents now plan to review relevant records and documents.
The attorney general said the investigation is in its earliest stages and no conclusions can be drawn at this point.
The statement did not identify the doctors.
Michael Jackson's death was a homicide caused primarily by the powerful anesthetic propofol and another sedative, the coroner announced Friday in a highly anticipated ruling that increases the likelihood of criminal charges against the pop star's personal doctor.
The Los Angeles County coroner's office determined the cause of death was "acute propofol intoxication." Other sedatives contributed to the death, most notably lorazepam, sold under the brand name Ativan. Additional drugs detected in Jackson's system were midazolam, diazepam, lidocaine and ephedrine.
The coroner did not release Jackson's full autopsy report, citing an ongoing security hold at the request of Los Angeles authorities as they continue investigating the case.
The 50-year-old Jackson died June 25 at his rented Los Angeles mansion. Dr. Conrad Murray, the Las Vegas cardiologist who was the pop star's personal physician, told police he gave Jackson propofol that morning after a series of sedatives failed to help Jackson sleep.
Murray has not been identified as a suspect but is the target of what police term a manslaughter investigation.
His lawyer criticized authorities Friday for withholding the full results of the singer's autopsy. Edward Chernoff said he's at a loss as to why the Los Angeles County coroner's office only released a brief summary of the results.
Chernoff said he needs to know precisely what levels of various drugs were detected.
"Release the toxicology report, the whole thing. Sunlight is the best disinfectant," Chernoff said. "This smells like gamesmanship."
Chernoff repeated his assertion that nothing Murray gave Jackson "should have" killed him.
Chernoff said his client was truthful with investigators and the general findings made public support statements the doctor gave investigators after Jackson's June 25 death.
Murray has been interviewed twice by police. According to court records, he told investigators that over about six hours he injected Jackson with two doses each of the sedatives lorazepam and midazolam. Finally, around 10:40 a.m., Murray said he succumbed to Jackson's demands and administered propofol, a drug Murray said he had given Jackson every night for six weeks.
Propofol, dubbed "milk of amnesia" among anesthesia professionals, is commonly used to render patients unconscious for surgery. It's only supposed to be administered by anesthesia professionals in medical settings and, because of its potency, requires the patient be closely monitored at all times. Using propofol strictly as a sleep agent violates medical guidelines.
Medical experts said the drugs found in Jackson's system magnify each other's effects.
"Instead of one plus one equals two, one plus one equals three," said Lee Cantrell, a toxicologist and director of the San Francisco division of the California Poison Control System.
A search warrant affidavit unsealed this week in Houston includes a detailed account of what detectives say Murray told them. The doctor said he'd been treating Jackson for insomnia for about six weeks with 50 milligrams of propofol every night via an intravenous drip, the affidavit said. Murray said he feared Jackson was becoming addicted to the anesthetic, which is supposed to be used only in hospitals and other advanced medical settings, so he had lowered the dose to 25 milligrams and added the sedatives lorazepam and midazolam.
That dosage is very small and by itself it's very unlikely it would have killed him. But with the other drugs there was a "benzodiazepine effect," according to the coroner, and it was deadly.
Dr. David Zvara, anesthesia chairman at the University of North Carolina at Chapel Hill, said it's difficult to determine what constitutes a fatal dose of propofol in someone receiving other sedatives.
"It's hard to set any level because of the way those act in synergy," he said. Given after the sedative lorazepam, "Even a small dose of propofol might have a very large effect."
Jackson had many medical procedures over the year and a long history with various drugs. Following his death, three medical professionals said Jackson asked them for propofol this spring. All refused. One, a registered nurse named Cherilyn Lee, recounted that Jackson told her he liked how the drug knocked him out fast and allowed him to sleep for hours longer than he could naturally.
Doctors were surprised by the coroner's mention of ephedrine, once sold as the controversial diet drug Ephedra and now banned by the federal Food and Drug Administration, though the drug can be used for resuscitation. Zvara said it's unlikely emergency personnel who responded to Jackson's home would have used that drug since epinephrine, otherwise known as adrenaline, is favoured.
Except for a brief video posted to YouTube, Murray has not spoken publicly since Jackson's death. In the video, he said: "I told the truth and I have faith the truth will prevail."
The Los Angeles district attorney's office has been working with the Los Angeles Police Department but has not indicated whether charges will be brought. The coroner's determination of homicide makes it more likely criminal charges will be filed but does not guarantee it.
Over the past seven years, just a handful of doctors have been convicted of manslaughter, mostly involving their patients' use of painkillers. To win a conviction, prosecutors would have to show that Murray acted recklessly and with negligence.
