Michael Jackson too heavily sedated to self-administer drug

Medical expert says Michael Jackson was too heavily sedated to have self-administered lethal dose of the sedative propofol.

While giving his testimony at the the involuntary manslaughter trial of the singer's physician, Dr Conrad Murray, Dr Steven Shafer said Michael Jackson could not have drugged himself.

Murray has denied all charges but Shafer also suggested that Murray gave the singer larger doses of the sedative than disclosed to the police.

Shafer suggested that the dose administered was not 25ml of propofol as claimed by Murray, but rather was 100ml.

The expert had helped write the propofol bottle guidance paper and said it was more likely that an IV propofol drip was administered to Jackson.

Leaving the singer on the drip may have caused his lungs to empty and the flowing propofol was not stopped even after Jackson was dead. This was one of the scenarios presented by Shafer.

"This fits all of the data in this case and I am not aware of a single piece of data that is inconsistent with this explanation," Shafer said.