Anesthesiology expert Dr. Steven Shafer demonstrates how propofol is extracted out of a glass bottle with a syringe during Dr. Conrad Murray's involuntary manslaughter trial, Wednesday, Oct. 19, 2011, in downtown Los Angeles
The trial of Dr. Conrad Murray, who is charged with involuntary manslaughter in the death of Michael Jackson, resumed Wednesday after more than three days. The prosecution continued to attempt to prove that the pop star’s physician improperly administered the anesthetic propofol, which subsequently led to his death in 2009.
Murray, who prosecutors say ignored warnings about the improper use of the drug, has pleaded not guilty in the case.
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Continuing his testimony from Friday, Dr. Steven Shafer, a professor of anesthesiology at Columbia University, told the court his interest in providing pro bono consultation on the case is to restore confidence in the public in the anesthetic and in the medical field.
“I am asked every day in the operating room, ‘Are you going to give me the drug that killed Michael Jackson?'” he said. “This is a fear that patients do not need to have.”
He later narrated a video shown to the court on the proper procedure in setting up an operating room, administering propofol and how to save a patient’s life in the event of a cardiac arrest.
Shafer is expected to be the prosecution’s last witness, but in the meantime, Murray’s defense was researching test results from the L.A. County Coroner on the amount of the sedative lorazepam found in Jackson’s body, which they contend he may have taken in the hours before his death without Murray’s knowledge.
Murray admits that he did give Jackson propofol, but his attorneys maintain, the amount was too small to have killed him.
The defense is expected to begin calling witnesses on Friday, including LAPD detectives, Murray’s character witnesses and Randy Phillips, who was promoter of the concert series Jackson was planning before he died.
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Madison Gray is Homepage Producer at TIME.com. Find him on Twitter at @madisonjgray. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.