Dr. Murray's Defense - Jackson Killed Himself

TMZ has learned Dr. Conrad Murray's legal defense is that Michael Jackson gave himself the fatal dose of Propofol.

Multiple sources familiar with the strategy tell TMZ the defense argument goes like this:

- At around 10:50 AM, Dr. Murray gave Jackson 25 mg of Propofol from a 20 ml bottle -- that's only about 1/8 of the bottle.

- The dose Dr. Murray administered would keep someone asleep for only 5 to 10 minutes, but the Propofol, along with the Ativan and Versed that was already in MJ's system, had a synergistic effect that put Jackson to sleep for a longer period of time.

- For the next hour, Dr. Murray stayed in the room and was on the phone for much of the time. Dr. Murray didn't leave the room to make the calls because MJ liked activity in the room, regularly sleeping with the lights on and cartoons blaring on the TV.

- At around noon, Dr. Murray left the room for approximately two minutes to go to the bathroom. While he was gone, the defense believes Jackson suddenly awakened and was frustrated he had spent nearly 9 hours trying in vain to sleep. The defense theory -- Jackson took the 20 ml bottle of Propofol and self-injected the remaining contents through the IV, causing a massive overdose that stopped his heart.

- Dr. Murray walked back in the room and saw Jackson with his eyes open and pupils dilated. Dr. Murray dropped the phone (he was speaking with his girlfriend) and began administering CPR.

The defense will argue Michael Jackson was a long-time Propofol addict -- something TMZ first reported shortly after the singer's death. As one source said, Jackson liked the sensation of Propofol being administered by IV, adding, "Michael liked to push it."

L.A. County Coroner's investigators took a picture in the room, showing an empty Propofol bottle on the floor, underneath the nightstand by Jackson's bed. The defense will argue Jackson grabbed the bottle from the nightstand, injected himself and then dropped the bottle.

Remember, law enforcement believes Dr. Murray hid bottles of Propofol before paramedics arrived. The defense will argue ... if Dr. Murray was really hiding Propofol, he would have removed the empty bottle under the nightstand that caused Jackson's death.

Ed Chernoff, Murray's attorney, could not be reached for comment.