Years after the singer's death, a medical authority on sleep disorders testified that Jackson likely suffered from an undiagnosed condition, which led to his overdose death in June 2009.
Dr. Charles Czeisler, a Harvard researcher, said Jackson was more than sleep deprived. In his opinion, Jackson had total sleep deprivation and his body was wasting.
Czeisler stated that the source of the problem was the very agent Jackson used to fall asleep. Czeisler told the jury that the surgical anesthetic propofol gave Jackson an illusion that he slept, but the way the substance works, the brain does not shut off to give the body rest. Jackson was not getting restorative sleep.
The propofol was administered nightly by Jackson's personal physician, Conrad Murray. Czeisler said the amount of propofol was "stupendous."
According pharmacy records, it was more than 4 gallons in less than 3 months -- enough for more than 7,000 major surgeries.
Czeisler was called by attorneys for Katherine Jackson, who is suing concert promoter, AEG Live. The plaintiffs contend that AEG executives hired Murray and ignored the pop star's health problems.
Czeisler says emails between AEG execs listed symptoms such as memory loss, failure to grasp dance moves, paranoia and chills.
The AEG attorney raised questions about AEG's role, asking Czeisler if he expects a concert promoter to diagnose a sleep disorder.
Czeisler said that if the concert promoter was aware that the artist was having difficulty sleeping, then he would expect that they would get the artist treatment.
About Jackson's role in caring for his own health, the defense referred to evidence that Jackson's use of propofol dated back to the 1990s and that Jackson rejected the recommendation of other doctors to seek a sleep disorder specialist.
Czeisler's response: No one can force anyone to be evaluated or treated.
The plaintiffs will call on a new witness on Monday.The Stanford University professor will testify about ethics.