LOS ANGELES (CBSLA.com) — A new witness took the stand Tuesday in the Michael Jackson wrongful death trial.

Drug addiction specialist Dr. Sidney Schnoll told the jury many times an addiction can be cured if a doctor gets to the root of the problem.

READ MORE: Report: US Rep. Karen Bass To Run For LA Mayor

Dr. Schnoll is an expert witness for the plaintiffs.

According to the Jackson family attorney, he will testify that instead of finding out what was wrong with Michael Jackson in the weeks and days leading up to his death, the singer’s doctor, Conrad Murray, instead kept him over-medicated, ultimately giving him an overdose of the powerful anesthetic that killed him.

Michael Jackson’s mother, Katherine Jackson, is suing concert giant AEG Live for negligence. The matriarch claims executives hired, retained or supervised Murray while the singer was preparing for his This Is It comeback tour.

The firm insists Murray was hired only at Jackson’s request.

READ MORE: On First Day Pfizer's Booster Available For Eligible Adults In LA County, Few Have Turned Up For The Shot

A human resources expert for the prosecution also finished her testimony Tuesday.

Jean Seawright told jurors AEG “did indeed fail to follow adequate hiring processes” when dealing with Murray.

She testified had officials at the firm done a credit check on the physician, executives would have seen he was deeply in debt and might have been motivated by his $150,000-a-month salary and not his patient’s well-being.

Attorneys for AEG produced guidelines from the U.S. Equal Employment Opportunity Commission (EEOC) that said financial background checks on potential employees can be discriminatory and to use caution before doing them.

MORE NEWS: Man Allegedly Tried To Run Over Members Of A Fairfax Synagogue With His Car Wednesday

Murray is currently serving a four-year sentence for involuntary manslaughter at an L.A. County jail following his conviction in Jackson’s 2009 death.