What Killed Brianna Negron and Casey DiStefano?

Casey and her mom at Disney World.

​In May, paramedics were called to Richard Lippner's Fort Lauderdale condo, where they found a young woman, 20-year-old Casey DiStefano, unconscious on the floor. It was the second time this had happened in four months. She wasn't breathing; her lips were blue. Lippner told police she had a history of seizures. Casey died at Holy Cross Hospital.

In an autopsy report obtained last week by The Juice, Casey's death was ruled an accident. Her official cause of death is "combined drug toxicity." In her system, investigators found Xanax, cocaine, marijuana, alcohol, oxycodone, and benzodiazepines -- an anti-anxiety drug such as Valium.

Brianna and her puppy.

​In late January, paramedics found 23-year-old Brianna Negron still and lifeless in the apartment of her ex-boyfriend, Richard Lippner. Her lips were blue, and she wasn't breathing. Lippner told police she'd been ill recently. He said she also had a problem with alcohol and drugs, showing police an empty prescription bottle with the label torn off.

Brianna never regained consciousness. Four days later, she died at the same hospital where Casey would.

Through his attorney, Lippner claims it's one giant coincidence, that he had nothing to do with either girl's death.

According to the medical examiner's report, Brianna died from organ failure brought on by pneumonia, complicated by the acute administration of Xanax. The report states that the cause of the illness was not apparent, but as a police source says, "Healthy 23-year-old girls don't just catch pneumonia in South Florida."

In her system, the medical examiner found Xanax, cocaine, marijuana, and oxycodone -- which could be either of the powerful prescription painkillers Oxycontin or Roxicet.

Her friends say that they were worried about Brianna, that they'd seen a downward spiral in her behavior following her breakup with a personal-injury attorney. Close friends brought her to the hospital three weeks before she died after she complained about throwing up and having difficulty breathing.

She was also still seeing Lippner once a week or so, according to several of Brianna's friends.

It's quite possible, say police, that her pneumonia was brought on by prolonged, sustained drug use. The autopsy report, finished less than two weeks before Casey died, says Brianna's death was an accident.

Lippner's lawyer, Melody Ridgley Fortunato, insists her client never gave either woman drugs.