Michael Jackson Autopsy Results Tighten Net Around Dr. Conrad Murray

July 28, 2009 -- It was reportedly a chaotic scene inside the bedroom of Michael Jackson on June 25 -- clothes strewn around the stifling hot room, handwritten notes papering the walls.

The King of Pop, for all intents and purposes, was dead -- killed, ABC News has learned, by a lethal cocktail of prescription drugs that included OxyContin and Demerol.

But according to The Associate Press, investigators believe it was Dr. Conrad Murray who injected the pop icon around midnight with propofol, the powerful anesthetic authorities believe ultimately killed him.

"This doctor is in serious trouble," criminal defense attorney Roy Black told "Good Morning America" today.

Murray, whose Houston office was raided by local and federal authorities last week, has already been named in court papers as the subject of a manslaughter investigation.

Toxicology reports are due to be released this week, and it seems the net is tightening on Murray, who remains secluded in his Las Vegas home.

"Everyone needs to take a breath and wait for these long-delayed toxicology results," Murray's lawyer, Ed Chernoff, said in a statement released Monday night. "Things tend to shake out when all the facts are made known, and I'm sure that will happen here as well."

But Chernoff has already admitted that Murray didn't call 911 for 30 minutes after he found Jackson unresponsive. And the doctor, who had been hired to monitor Jackson for his planned "This Is It" tour, initially performed CPR while Jackson was lying on a bed, not on a hard surface as is proper protocol.

Black told "Good Morning America" that if Murray is charged it will be up to his defense to prove there was a sound medical reason why he prescribed and administered the off-label use of a drug that is meant for use in the operating room.

"They're going to say there's not legitimate reason to prescribe this drug for use in the home," he said. "It certainly should not be used for insomnia."

An official close to the investigation told The Associated Press that Jackson relied on propofol like an alarm clock, instructing doctors to stop the IV when he wanted to wake up. It's a drug authorities believe he may have been using for two years.