Michael Jackson caused his own death, Dr. Conrad Murray's defense says

(CBS/AP) LOS ANGELES - A lawyer for Dr. Conrad Murray, who is charged in the death of Michael Jackson, says the pop superstar caused his own death.

Pictures: Who's who in the trial of Dr. Conrad Murray

Video: Dr. Conrad Murray manslaughter trial begins

He also claimed Jackson self-ingested the anesthetic propofol, creating a "perfect storm in his body" that killed him instantly.

Chernoff told jurors it was not their job to determine whether Murray was a good doctor. He said Murray and Jackson were actually friends and Murray was trying to wean Jackson off of propofol. Jackson, however, took a lethal dose before he died, the lawyer said.

At times during Chernoff's opening statement Murray appeared to be crying and wiped his eyes with a tissue.

The defense's remarks came after more than an hour of opening arguments by prosecutors who laid out their case against the Houston-based cardiologist with a multimedia presentation which featured an audio recording Murray made of Jackson under the influence of propofol, and an image of the pop star's pale body lying on a gurney after he died from an overdose on the drug on June 25, 2009.

Murray has pleaded not guilty to involuntary manslaughter and he and his attorneys have denied he gave Jackson anything that should have killed the pop superstar.

A number of Jackson's family members were in the courthouse for opening arguments, including his father Joseph, mother Katherine, sisters LaToya and Janet, and brothers Jermaine, Randy, and Tito.

LaToya Jackson carried a sunflower, Michael's favorite flower.

Murray arrived holding hands with his mother. If convicted, he faces up to four years in prison and the loss of his medical license.

Complete coverage of the Michael Jackson - Dr. Conrad Murray case on Crimesider