Michael Jackson could still have been saved after he stopped breathing if the doctor now charged in his death had properly called for help and taken steps to resuscitate him, a cardiologist testified Wednesday in Dr. Conrad Murray's involuntary manslaughter trial.

Dr. Alon Steinberg, who reviewed Murray's treatment of Jackson for the California Medical Board, agreed under questioning by a prosecutor that the physician's care amounted to gross negligence. Steinberg testified the doctor's interview with police led him to the opinion that Jackson was "savable" when Murray discovered the singer had stopped breathing after using the surgical anesthetic propofol in 2009.

During cross-examination by defense attorney Michael Flanagan, Steinberg said Murray's recollection that his patient had a pulse, a heart rate and was warm to the touch meant that Jackson could have been saved if the doctor had immediately called 911.

"It makes logical sense to call 911 if he doesn't have any of the appropriate equipment," Steinberg said.

One of the number of things that Murray failed to do, Steinberg said, was get his patient's written, informed consent before administering a powerful anesthetic in an unmonitored, risky setting. Any logical person, if informed of the risks, would have declined the drug, the witness said.

Flanagan asked, to much objection from a prosecutor, whether he was aware of Jackson's drug use or that he was a "habitual user" of the narcotic Demerol.

Jackson's brother, Randy, muttered from the audience: "That's not true."

The judge barred most of that line of questioning, but did allow the attorney to ask, "When you make these conclusions ... do you know specifically anything about Mr. Jackson's propensities toward drugs?"

"No," Steinberg responded.

Flanagan also asked the witness about a 2010 study in China on the successful use of propofol on patients with severe insomnia. Steinberg said that because the study had not been published when Murray was treating Jackson with propofol in early 2009, the doctor's use of the drug was unethical.

"He was basically doing primary research with no overview," he said.