Lawyer: Concert Promoter Pushed Michael Jackson Despite Rx Drug Struggle

Michael Jackson's children expected to testify about his final days.

April 29, 2013— -- Michael Jackson's family and friends knew the King of Pop abused prescription drugs, an attorney for Jackson's mother told a Los Angeles jury today, yet the promoters of his ill-fated 2009 comeback tour denied any knowledge of it.

In his opening statements today, attorney Brian Panish, who is representing Katherine Jackson in her wrongful death lawsuit against AEG Live, told jurors that officials with the concert promoter were so focused on beating the competition with Jackson's "This Is It" tour that they relentlessly pushed the King of Pop to perform despite numerous warning signs about his health, and negligently hired Dr. Conrad Murray, the man convicted of involuntary manslaughter for giving Jackson a fatal dose of the anesthetic propofol.

"They wanted to be No. 1 at all costs," Panish said. "We're not looking for any sympathy... We're looking for truth and justice."

Panish detailed Jackson's prescription drug abuse history, saying the singer regularly used demerol and propofol, and that "people who knew him believed he had a problem with prescription medication."

"[Michael Jackson's] stirring voice, his musical genius, his creativity and his generosity and his huge heart was extinguished forever," Panish said. "You're going to hear the whole story about what happened in the death of Michael Jackson."

AEG officials have denied all wrongdoing in the civil suit filed by Katherine Jackson and the singer's three children, saying that Murray, who was found guilty of involuntary manslaughter in 2011, was an independent contractor hired by Jackson.

Marvin S. Putnam, the lawyer representing AEG Live, told jurors in his opening remarks today that the concert promoter officials could not have known about Jackson's private life, including his propofol use, and could not have foreseen circumstances that led to a physician giving the pop star doses of the anesthetic as a sleep aid.

"The truth is, Michael Jackson fooled everyone," Putnam said. "He made sure that no one, nobody, knew his deepest darkest secrets."

Murray is currently serving four years in prison for his role in the pop superstar's death and is appealing his conviction.

Katherine Jackson and two of her children, Rebbie and Randy Jackson, sat in the front row of the courtroom, as Jackson fans and media thronged the hallways and the areas outside the courthouse. No cameras were allowed inside the courtroom.

Tens of millions of dollars, not to mention the worldwide pop music icon's reputation, are at stake in this trial. A jury comprised of six men and six women will hear arguments that are expected to last into the summer to decide if AEG is liable for damages.

The case is expected to delve into the highly guarded personal life of Jackson, who died at age 50 four years ago, and provide the most in-depth details of the superstar's final days. The trial is expected to include detailed testimony about other doctors' treatment of Jackson, a subject that was largely off-limits in the criminal case.

"I think this case is important because in the Conrad Murray case, I think everyone believes we got part of the story of Michael Jackson. This trial is important because we will get the rest of the story," HLN anchor Vinnie Politan told ABC News.

A who's who of Hollywood was lining up to support the Jackson family. The expected star-studded witness list included Quincy Jones, Diana Ross, Lou Ferrigno and Spike Lee. Both of Jackson's ex-wives, Lisa Marie Presley and Debbie Rowe, were listed as potential witnesses.

In recent days, Rowe, the biological mother of Jackson's two eldest kids -- Prince, 16, and Paris, 15 -- has been photographed spending time with her daughter.

Prince and Paris are expected to testify about their father's final days leading up to his 2009 overdose death. Their testimony is expected to be the emotional tipping point of the trial as they can give a rare glimpse inside their once-secret world with their famous father.

Attorneys for the Jackson family denied media reports that they were seeking $40 billion in damages. However, damages might run into the billions if AEG Live is found liable.

"Michael Jackson -- the biggest star in the world -- you're talking about what his life was worth from the point that he died, forward, how much could he have made," Politan said.

ABC News' David Wright and Natasha Singh, and the Associated Press, contributed to this report