Why Are Michael Jackson Autopsy Results Taking So Long?

'Especially in a case like this, you want to make sure you have it right,' coroner's spokesperson says.

Almost a month has passed since [artist id="1102"]Michael Jackson's[/artist] death, and we still don't have a definitive answer about what killed the 50-year-old King of Pop. After an initial autopsy, the cause of death was deferred in order to complete more toxicology tests. On Thursday, the Los Angeles County coroner's office said it could take another two weeks to get the results of those tests before determining what might have caused the singer to go into cardiac arrest on June 25 at his Los Angeles home.

It's typical for medical examiners to wait up to a month to announce such results in high-profile cases, but why exactly is the Jackson inquiry taking so long?

For answers, we turned to Dr. Joshua Perper, Chief Medical Examiner for Broward County, Florida — and the man the world came to know as the lead forensic investigator in the probe into the death of Anna Nicole Smith two years ago.

Because the Jackson death has such worldwide interest, Perper said the coroner's officials want to make sure they don't overlook anything in their investigation.

"They want to make sure they aren't missing any additional drugs that might be in the system but are more difficult to detect," said Perper, who has no first-hand knowledge of the case. "They might take more tests than what they thought initially was necessary, because perhaps they found some level of drugs so far that are not sufficient to explain the death."

Perper said some drugs are not always evident in preliminary screenings. Jackson was reported to have been taking a number of anti-anxiety and painkilling prescription medications, as well as the anesthetic Diprivan at the time of his death, and based on interviews with Jackson physicians and witnesses, investigators may be expanding the screen to include other drugs.

As an example, he cited his own experience in the Smith case, in which the sleep medication chloral hydrate did not initially come up in the former Playboy playmate's system, but was screened for after an interview with one of her physicians.

"[In the Jackson case] either the testing so far doesn't disclose a cause of death, or not a sufficient amount [of drugs] to explain a cause of death, so they are expanding the tests," he said, noting that it does not typically take this long to reach a conclusion. "They want to make sure in this case that they don't have to swallow a statement later or have someone repeat the tests and find drugs that they didn't find."

Craig Harvey, the spokesperson for the Los Angeles County Coroner's Office, told MTV News on Friday that his department stated on June 26 that results could take up to six weeks and that, as of now, they are on target. "Right now it's not so much a matter of results coming in but final reports being prepared and ready," Harvey explained. "We don't release preliminary reports, and we don't release anything until everything is finalized."

Harvey said officials are waiting for some of those final reports to come in and be assessed, agreeing with Perper's suggestion that haste is not wise in such a high-profile case. "Especially in a case like this, you want to make sure you have it right, because as we say, you only get one shot," he said. "So, when you do finally release the results, you what to make sure you're convinced by them and comfortable with what you're releasing."

Asked about the reports of Jackson's alleged use of the fast-acting Diprivan, an anesthetic not intended for use outside of the supervision of a trained anesthesiologist in a doctor's office, Perper said that while the drug does leave the system quickly, it's unlikely that investigators will not find some traces of it if Jackson used it before his death.

The 15-year-veteran of the Broward County coroner's office said investigators are likely looking at blood, bile, urine, eye and cerebrospinal fluid, as well as testing the liver, kidneys and brain. "The medical examiner's office doesn't have all the capabilities to test everything," he said. "There are some very esoteric substances and unusual testing methods that have to be sent to specialty labs."

Harvey would not discuss specifics of the case, but did say that coroner's office officials have had discussions with some of Jackson's physicians and pursued medical records on their own, even as Los Angeles police chase some of the same leads in their probe of the singer's death. On Thursday, a spokesperson for the Los Angeles District Attorney's office confirmed that the police investigation is criminal in nature, a week after the LAPD's chief said it's possible the probe could turn into a murder case depending on findings.

Even after all that legwork, Harvey said it is possible that officials will never know what killed Jackson. "In a small percentage of cases, we find no cause of death after the autopsy," he said. "But we will have something to announce at the end, even if we don't find anything at all." 

For complete coverage of the life, career and passing of the legendary entertainer, visit "Michael Jackson Remembered."

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