Photo of Demi Cuccia, 16, released by the family.
PITTSBURGH (CBS/AP) A teenager who fatally stabbed his 16-year-old cheerleader girlfriend claims his acne medication made him do it.
Prosecutors say John Mullarkey, now 20, told police he had been suffering mood swings caused by pimple medicine in the months before the August 15, 2007 murder of Demi Cuccia, his on-again, off-again girlfriend. Mullarkey then slashed his own throat in the moments after the killing.
Mullarkey had apparently gone to Cuccia's home in suburban Pittsburgh that night to reconcile with her, but he brought a hunting knife with him, according to prosecutors.
He allegedly stabbed Cuccia 16 times, mostly in the upper left chest, arm and shoulder, with a 3.5-inch folding knife, before slashing a 10-inch gash across his own throat. Mullarkey's murder trial opened on Tuesday.
In opening arguments, Allegheny County Deputy District Attorney Mark Tranquilli said Mullarkey essentially spelled out his defense when he used an eraser board to communicate with a county homicide detective while lying in the hospital days after the crime.
"If I did something — no, erase that — if somebody did something bad and they were taking medication, would that be a defense?" Tranquilli said Mullarkey wrote that day.
Mullarkey's defense attorney, Robert Stewart, contends the defendant started taking Accutane about four months before the killing. Stewart stopped short of blaming the stabbing on the drug, but he said he'll present evidence that Mullarkey had told friends he was concerned about the drug's effect on his moods, among other things.
Accutane is prescribed as an acne drug of last resort because the U.S. Food and Drug Administration has linked it to episodes of suicide and depression. It's made by Hoffmann-La Roche Inc., of Nutley, N.J., whose Web site says the drug can cause "serious mental health problems" including depression, suicide and psychosis, defined on the site as "seeing or hearing things that are not real."
Stewart also said Mullarkey had the knife with him only because he's an avid hunter who has carried it since he was a Boy Scout.
That's important because the issue at trial isn't whether Mullarkey stabbed Cuccia, but what his frame of mind was at the time. Under Pennsylvania law, "premeditation" isn't defined as plotting but rather as a realization — however momentary — that one's actions could kill someone.
Tranquilli told jurors that just stabbing Cuccia 16 times is evidence of premeditation. He said that the cheerleader bled to death from a shoulder wound and that some wounds were so vicious they were deeper than the blade's length.
"Somewhere along the continuum of 16 stabs you decide to murder someone," Tranquilli said.
But Stewart suggested to the jury that third-degree murder, a killing with malice but no premeditation, or voluntary manslaughter, a killing in the heat of passion, would be more appropriate verdicts.
First-degree murder carries life in prison without parole. Third-degree murder has a maximum 20- to 40-year prison sentence and manslaughter carries 10 to 20 years.
Stewart said the killing resulted from an "unfortunate combination of factors," one of which was the medicine.
The trial is expected to last about two days.