Updated

A prosecutor said a California doctor facing rare murder charges in the drug deaths of three men under her care said she knew three previous patients had died from drug overdoses.

At a preliminary hearing set to resume Tuesday, Deputy District Attorney John Niedermann cited the other deaths, which he said would show a pattern of behavior by Dr. Hsui-Ying "Lisa" Tseng.

"It put her on notice that the prescriptions she was providing were leading to deaths," Niedermann said at the abbreviated Monday session of the hearing to determine whether Tseng will stand trial.

Tseng sat at the counsel table clad in an orange jail jumpsuit with shackles at her ankles as the first witness, her former office receptionist, testified about the workings of her busy medical office in Rowland Heights.

No charges were filed in those earlier drug overdoses, which Tseng learned about in 2007 and 2008, but the prosecution seeks to use them as evidence against her. She is charged in the deaths of three young men who allegedly overdosed after receiving prescriptions from her for painkillers and anti-anxiety medications.

She is charged with second-degree murder and could be sentenced to 45 years to life in prison if convicted.

Tseng has pleaded not guilty to 24 felony counts. Authorities allege she wrote more than 27,000 prescriptions over a three-year period. She is among only a handful of doctors nationwide to be charged with murder related to prescription drugs.

Tseng was represented by five attorneys, an indication of the seriousness of the case.

She has been in custody since her arrest in March. She is being held on $3 million bail in spite of her attorneys' previous arguments that she is a mother of small children who has ties to her community. The judge refused to reduce her bail at that time.

In the courtroom audience was the mother of one of the young men who died. April Rovero's son, Joey, died after receiving prescriptions from Tseng. The 21-yearold University of Arizona student drove to California with friends to get prescriptions from Tseng in 2009.

April Rovero founded the National Coalition Against Prescription Drug Abuse. She promised to be in court every day.