The witnesses — drug addiction specialist Dr. Robert Waldman and propofol expert Dr. Paul White — are expected to be the final defense witnesses unless Murray decides to testify on his own behalf about the circumstances surrounding Michael Jackson's death.

White, a prominent anesthesiologist, has been accused of calling a prosecution expert a "scumbag," an allegation that prompted a judge to consider contempt of court charges.

FULL COVERAGE: The Conrad Murray trial

White denied making the remark, but acknowledged that he made other critical comments about Dr. Steven Shafer, a New York anesthesiologist with whom he has had a long and previously amicable professional relationship.

"I am going to take the high road, not the low road with him," E! Online's website quoted White as saying. "I was his teacher when he was a medical student. The truth will come out. It always does."

Judge Michael Pastor chided White for the remarks, telling him he has "no business making any of those comments."

White's testimony is crucial to the defense, which must counter Shafer's blistering testimony.

Shafer said that mathematical modeling debunked Murray's statement that he had given Jackson a single 25-milligram dose of propofol before his death. Instead, Jackson received 40 times that amount of the surgical anesthetic, Shafer testified. He also said that even if Jackson gave himself the fatal dose, Murray was "responsible for every drop of propofol in that room."

The defense team has been moving quickly through its short witness list. On Wednesday, the jury heard from five of Murray's former patients. The character witnesses described a generous, caring doctor who helped treat the poor.