Dr. Lisa Tseng: Murder Conviction, Sentence, and Appeal

The Dr. Lisa Tseng case is the 2015 Los Angeles prosecution in which Hsiu Ying “Lisa” Tseng, a Rowland Heights osteopathic physician, became the first doctor in the United States convicted of murder for overprescribing drugs. A jury found her guilty of three counts of second-degree murder in the overdose deaths of three young male patients, along with 19 counts of unlawfully prescribing controlled substances and one count of obtaining a controlled substance by fraud. In February 2016, Los Angeles Superior Court Judge George G. Lomeli sentenced her to 30 years to life in state prison, where she remains incarcerated.¹²

The Three Deaths Behind the Murder Charges

All three victims were young men who died of drug overdoses in 2009 after receiving prescriptions from Tseng.

Vu Nguyen, 28, of Lake Forest, had been a patient since August 2008, seeking treatment for back and neck pain. Tseng prescribed him Xanax, Norco, Opana, and Adderall. He died on March 2, 2009, from the combined effects of Opana, Xanax, and methadone.³

Steven Ogle, 24, of Palm Desert, first saw Tseng in March 2009. He told her he had been using heroin and taking 80mg OxyContin tablets daily. She prescribed methadone and Xanax. He died on April 9, 2009, of methadone intoxication.¹

Joseph Rovero, 21, an Arizona State University student from San Ramon, saw Tseng only once, on December 9, 2009. He told her he was taking high daily doses of OxyContin, Xanax, and Soma. She prescribed Roxicodone, Soma, and Xanax. Nine days later he died of combined drug toxicity involving alcohol, prescription opioids, Soma, and Xanax.³

At least six additional Tseng patients between 21 and 34 years old died of overdoses between 2007 and 2009, often within one to four days of filling her prescriptions. Prosecutors introduced those deaths at trial as evidence Tseng knew her practice was killing people.³

How the Clinic Operated

Tseng graduated from Michigan State University College of Osteopathic Medicine and was licensed in 1997.⁴ In 2005 she opened Advanced Care AAA Medical, a storefront clinic on Fullerton Road in Rowland Heights, initially serving local Hispanic and Asian communities as a general practice.

By 2008 the clinic looked nothing like a family medical office. The patient base had shifted to white men in their twenties and thirties driving in from outside Los Angeles County. Nearly all paid in cash. Fees doubled, waits stretched to six hours, and one visitor described the scene as looking “like a parole office.” Daily gross receipts climbed from about $600 to between $2,000 and $3,000. Between 2007 and 2010 the clinic took in roughly $5 million.³

Tseng typically spent ten to fifteen minutes with new patients and five minutes on return visits, sometimes seeing multiple unrelated patients in the same exam room. She frequently skipped physical exams, failed to take medical histories, and did not check the CURES database, California’s prescription drug monitoring system, to see whether patients were doctor-shopping. She prescribed oxycodone, oxymorphone (Opana), fentanyl, hydrocodone, methadone, Xanax, Soma, and Adderall in combinations that experts later called an “extreme departure from the standard of medical care.”³

Over a three-year period ending in February 2010, Tseng wrote more than 27,000 prescriptions for controlled substances, roughly 25 per day.⁵³

The Warnings She Ignored

The DEA had been looking at Tseng since 2007, alerted by pharmacies and Murrieta police about the volume of oxycodone she was moving to patients with no apparent medical need. A state prescription database review showed she was prescribing to many of the same patients as another physician who had already been federally indicted.⁵

Beginning in 2008, coroner’s investigators and law enforcement contacted Tseng directly to tell her patients were dying of suspected overdoses shortly after her prescriptions were filled. Her response was to add “alerts” to those patients’ electronic records noting a possible overdose death. She later altered digital records to insert examination notes that had not been there when investigators first seized the files. And she kept prescribing.³

In August 2010, DEA agents and California Medical Board investigators raided the clinic, seized files and computers, and served an Immediate Suspension Order stripping Tseng of her authority to prescribe controlled substances. The DEA declared her an “imminent danger to public health and safety.”⁶ Dr. James L. Gagne, a medical expert who reviewed her prescribing, told authorities it was “inconceivable” that her patterns reflected legitimate medicine and that he was “almost certain” she was prescribing to addicts or dealers.⁵

Tseng surrendered her medical license to the Osteopathic Medical Board of California and was arrested in March 2012.⁷ She had already settled five wrongful-death lawsuits from patient overdoses before criminal charges were filed.⁸

Why the Charge Was Murder, Not Manslaughter

The six-week trial in Los Angeles County Superior Court was prosecuted by Deputy District Attorneys John Niedermann and Grace Rai.⁹ Everything turned on the legal theory of implied malice. To prove second-degree murder, prosecutors had to show that Tseng, as a licensed physician, was subjectively aware her conduct created a high probability of death and consciously disregarded that risk.³

The evidence of her state of mind was blunt. In recorded conversations with undercover DEA agents, Tseng called 80mg OxyContin “super high” and Norco “evil,” and acknowledged that such opioids were typically reserved for cancer patients or those with broken bones. She privately referred to her own patients as “druggies.” She kept prescribing anyway, and she kept prescribing after being contacted about eight prior patient overdose deaths.³

The defense argued the evidence showed negligence, not murder. Her attorneys said she lacked a “reckless mindset,” pointed out that investigators had never explicitly told her she was legally responsible for any deaths, and argued that other substances in two victims’ systems were an intervening cause that broke the chain of criminal responsibility.¹⁰

On October 30, 2015, a jury of ten women and two men convicted Tseng on every count. Los Angeles District Attorney Jackie Lacey called it the “most severe penalty we have ever gotten on a doctor who illegally overprescribed drugs to patients.”⁶

The Sentence

On February 5, 2016, Judge Lomeli sentenced Tseng to 30 years to life. She is not eligible for parole until she has served the full 30 years.¹¹

Lomeli described the practice as a reckless “assembly line” that generated millions while causing immense suffering, and said Tseng was still trying to deflect responsibility even as she accepted some blame. Tseng apologized to the families in court, said she felt “shameful and remorseful,” and claimed she had been in denial and lacked sufficient training in prescribing addictive narcotics. April Rovero, Joey Rovero’s mother, had written to the judge describing the shock of preparing for her son’s funeral instead of his homecoming from college, and asked for the maximum sentence.¹¹

The Appeal

Tseng appealed to the California Court of Appeal, raising five issues that included the sufficiency of the implied-malice evidence, the admission of the six uncharged patient deaths, a challenge to a financial-records search warrant, alleged prosecutorial misconduct, and a sentencing question about multiple punishments for the same act.¹²

The appellate court rejected every argument and affirmed the judgment. On implied malice, it acknowledged that a departure from the medical standard of care alone cannot support a murder conviction, but held that Tseng’s case was different in kind: she had expert knowledge that the drug combinations she prescribed were potentially lethal, she knew her patients were drug-seeking, and she had been told repeatedly by pharmacies, coroners, and law enforcement that patients were dying. The pattern showed the “subjective mental state” and “conscious disregard for life” required for second-degree murder. The court also agreed with the jury that other substances found in two victims’ systems did not amount to an “exonerating, superseding cause.”³¹⁰

Why the Case Mattered

The conviction was widely described as the first time in the United States a doctor was convicted of murder for overprescribing drugs.¹³ The appellate opinion noted that physician murder prosecutions were rare and pointed to People v. Klvana (1992), a California case in which an obstetrician’s second-degree murder convictions for infant deaths were upheld on the same implied-malice theory.³

Arriving in the middle of the national opioid crisis, the case reshaped how prosecutors approached pill mills. Niedermann’s work helped make the Los Angeles District Attorney’s office a leader in those prosecutions and emboldened other offices to pursue similar charges.⁹ Medical commentators, meanwhile, warned of a potential chilling effect on legitimate pain management, though experts generally characterized Tseng’s prescribing as an outlier unlikely to expose ordinary physicians to criminal liability. The line between civil malpractice and criminal responsibility, they cautioned, remains poorly defined.¹⁴

Where Tseng Is Now

Tseng has been in continuous custody since her March 2012 arrest. Under the 30-years-to-life sentence, she will not become eligible for parole consideration until approximately 2046. As of 2025 she remains incarcerated in a California state prison.²

1
DEA. Doctor Receives 30 Years to Life in Prescription Drug Overdose Case
2
California Coalition for Women Prisoners. Newsletter Issue 76
3
California Attorney General. People v. Tseng Appellate Opinion
4
MedCentral. Lessons From the Murder Conviction of Dr. Hsiu-Ying Lisa Tseng
5
Los Angeles Times. DEA Raids Doctor’s Office in Rowland Heights
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DEA. Doctor Convicted of Three Murders in Prescription Drug Overdose Case
7
ABC News. California Doctor Charged With Murder in Prescription Drug Deaths
8
ABC7 Los Angeles. Testimony in Murder Trial of Rowland Heights Doctor Focuses on Video
9
Los Angeles Times. Prosecutor in Landmark Doctor Murder Case
10
CAP Central. People v. Tseng
11
CNN. California Overdose Doctor Gets 30 Years to Life
12
FindLaw. People v. Tseng
13
The Rheumatologist. California Doctor Gets 30 Years to Life in Landmark Overdose Case
14
National Center for Biotechnology Information. Criminal Prosecution of Physicians for Opioid Prescribing