Michael Jackson doctor declines to testify. Was that his last, best chance?

After 22 days of intense testimony, both the prosecution and the defense rested their cases on Tuesday in the involuntary murder trial of Michael Jackson’s former physician, Conrad Murray.

The announcements came after a brief, dramatic moment when the king of pop’s former doctor was asked by Superior Court Judge Michael Pastor whether he wanted to testify on his own behalf.

Dr. Murray, a Las Vegas cardiologist, informed the judge, outside the jury’s presence, that he did not wish to take the stand.

Murray might have made a sympathetic witness had he chosen to express his grief over the loss of Jackson, whom he has called a close friend. But trial analysts note that he would have come under blistering cross examination by Deputy District Attorney David Walgren, who would highlight every unanswered question about Jackson’s death.

Closing arguments in the case are set to begin on Thursday at the Los Angeles County Courthouse. Jury deliberations will likely begin later that day.

The high-profile case featured a clash of medical experts and two sharply divergent theories of what may have happened in the final hours of Mr. Jackson’s life on June 25, 2009.

Murray was charged with administering a lethal dose of the anesthetic propofol in an effort to help treat Jackson’s chronic insomnia. He faces up to four years in prison if convicted and loss of his medical license.

Prosecutors and their experts maintain that Murray set up an automatic drip of the anesthetic and that he became distracted while visiting a rest room and making telephone calls. At some point, they say, Jackson stopped breathing and died. They say Murray is responsible for the death, not only because he administered the drugs found in Jackson’s system, but also because he left the bedside of his heavily-sedated patient.

One prosecution expert said Murray’s actions were akin to leaving a sleeping infant on a kitchen counter.

Defense lawyers and their experts offered a completely different scenario. They suggested that Jackson self-administered a fatal combination of sedatives and propofol in a desperate attempt to get some sleep. They noted that Jackson told Murray that he enjoyed injecting propofol into his system, and they speculated that Jackson awakened while Murray was out of the room or distracted, and pushed a fast injection of the anesthetic into his system. The propofol concentration may have instantly stopped his heart, a defense expert testified.

In the contest between dueling medical experts, the prosecution appears to have scored a major victory. Dr. Steven Shafer, an anesthesiology specialist at Columbia University, converted the courtroom into a classroom, leading the jurors through the potentially confusing world of sedation and anesthetics, all the while explaining routine safeguards that Murray by-passed or ignored.

Dr. Shafer likely scored major points when jurors learned that as a matter of policy he does not charge a fee for his work on cases like Jackson’s.

In contrast, defense expert Dr. Paul White, also a well-respected anesthesiologist and research scientist, testified that he had been paid $11,000 for a portion of his work. He noted that he would not charge his usual fee because he said he did not believe the defense could pay it.

Although Dr. White tried to undercut Shafer’s analysis, White seemed handcuffed by the burden of having to justify some of the shoddy and questionable practices allegedly undertaken by Murray.

At one point he was asked about Murray’s 20-minute delay in calling 911. White suggested that a doctor might not have time initially – in the first few minutes of an emergency – to make the call himself. But White never offered an explanation of why it might be better to wait 20 minutes as Murray did.

Asked whether Murray should have told the responding paramedics – and later, the emergency room doctors – that he had administered propofol to Jackson prior to the incident – White said it wasn’t necessary to Jackson’s emergency treatment because the effect of the propofol would have been greatly reduced by then.

The response did little to remove the strong suggestion that Murray was trying to cover up his conduct.

A number of medical experts testified that propofol was not a recognized sleep aid. They said it should never be administered in a bedroom as had been the case with Jackson. They stressed that propofol is almost always administered in a hospital or clinic with a full array of monitoring and resuscitation equipment close at hand.

In one illustration of the weakness of the defense case, Deputy District Attorney Walgren asked White, the defense expert, whether he would administer propofol in a private bedroom as Murray had done to Jackson.

“I would never administer propofol in a bedroom,” the defense expert said.