Michael Jackson’s doctor has pleaded not guilty to involuntary manslaughter over the death of the pop star at a brief hearing in Los Angeles.

Dr Conrad Murray, accused of giving Jackson a fatal dose of an anaesthetic to help him sleep, appeared in court as Jackson’s father Joe, mother Katherine, and siblings LaToya, Jermaine, Tito, Jackie and Randy watched from courtroom seats behind prosecutors.

Neither Murray nor the Jacksons showed much emotion as Murray entered his plea through his attorney Ed Chernoff, but as he emerged from court, Joe Jackson declared: “My son was murdered. We need justice.”

Joe Jackson told CNN’s Larry King that he doesn’t believe Murray is the only person responsible for his son’s death.

“To me, he’s just the fall guy. There’s other people I think involved with this whole thing,” Joe Jackson said, without elaborating.

Murray, 56, a Houston cardiologist who was with Jackson when he died on June 25, entered his plea just hours after he was charged.

Superior Court Judge Keith L. Schwartz set bail at 75,000 US dollars, three times more than the amount people normally face after being charged with involuntary manslaughter.

Murray posted the bail about two hours later and was released.