LOS ANGELES, Calif. — A six-man, six-woman jury was seated today in the trial of Katherine Jackson’s $40 billion negligent-hiring lawsuit against the promoters of her late son Michael Jackson’s ill-fated London concert series over Conrad Murray’s work as the pop superstar’s personal physician.

Attorneys in the case still need to pick alternate jurors for the trial, which is expected to last about three months.

Jackson contends in her lawsuit, filed in September 2010, that AEG Live was liable for hiring Murray to be the pop star’s personal physician. Murray administered propofol — a powerful sedative — to Jackson, who died June 25, 2009, at age 50 of acute propofol intoxication. Jackson was staying at a rented Holmby Hills estate while he was rehearsing for the London concerts.

Murray was convicted of involuntary manslaughter in Jackson’s death and was sentenced in November 2011 to four years in the Los Angeles County jail.

AEG attorneys have denied any wrongdoing and contended that the pop superstar had a drug problem long before he agreed to the London concerts.

Katherine Jackson’s lawsuit was filed on behalf of herself and her son’s three children, Michael Jr., Paris-Michael Katherine and Prince Michael.

AEG Live attorney Marvin Putnam has maintained that his clients never hired Murray and that the cardiologist, in fact, had been one of many doctors who treated the singer in the past. Putnam also said Jackson had a drug problem for years before he entered into any agreements to perform on behalf of AEG Live.

Putnam said a proposed contract between Murray and AEG Live was never executed before Jackson’s death. However, a judge found that a contract could be implied by various actions taken by the company, including discussions to pay him $150,000 a month.

Attorneys for the Jacksons maintain that AEG Live, in allegedly hiring Murray, gave little consideration to red flags showing that the doctor was in debt and was not a board-certified cardiologist.

On March 1, Los Angeles Superior Court Judge Yvette Palazuelos pared the case, tossing aside all other claims that could hold AEG Live liable for Jackson’s death. Defense attorneys had moved for dismissal of the entire complaint, saying that two years of litigation failed to show the company or its executives did anything wrong.

Palazuelos dismissed Timothy Leiweke, AEG Inc.’s former president and chief executive officer, and that company as defendants. But her final ruling kept Paul Gongaware, co-chief executive officer of Concerts West (a division of AEG Live) and AEG Live President and Chief Executive Officer Brandon Phillips in the case.

Gongaware stated in a sworn declaration that he never told Jackson or any of his doctors what medications the singer should take.

“At no point did I ever require Jackson to take propofol,” Gongaware stated. “I had no idea Jackson was taking propofol until after I learned how Jackson died in press reports. I had no suspicions whatsoever that Dr. Murray was giving Jackson propofol.”

But the Jackson attorneys point to an email Gongaware penned less than two weeks before Jackson died to tour director Kenny Ortega after the latter expressed concerns that Murray had kept Jackson from a rehearsal the day before.

“We want to remind (Murray) that it is AEG, not MJ, who is paying his salary,” Gongaware wrote. “We want to remind him what is expected of him.”