LOS ANGELES (CBSLA.com/AP) — Jury deliberations began Monday in the trial of a Rowland Heights doctor charged with the drug-overdose deaths of three patients.

According to the Los Angeles County District Attorney’s Office, Dr. Lisa Tseng, 45, faces three counts of second-degree murder.

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Tseng is accused of running a pill mill and prescribing powerful painkillers to three of her patients who subsequently overdosed.

According to prosecutors, Tseng allegedly handed out more than 27,000 prescriptions to known addicts.

However, defense attorney’s have argued she was just being a compassionate doctor.

In September 2007, a coroner notified Tseng of her first patient death just two days after he had gotten prescriptions from her for Oxycodone, Xanax and Soma, according to prosecutors.

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Tseng’s next patient died six months later. Jurors were shown a picture of his body, lying face-down in his bed.

A third patient overdosed in Tseng’s clinic.

In total, 12 of Tseng’s patients have died, but only three were the subject of murder charges because other factors were involved in the other deaths.

All of the victims were young men, authorities added.

If convicted, Tseng could face a maximum sentence of up to life in prison.

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