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A jury found a south Florida teenager guilty of attempted murder on Monday for the severe beating of a middle-school girl in 2010 that left her with permanent brain damage, rejecting his claim of insanity.
Wayne Treacy, 17, faces up to 50 years in prison for the attack on then-15-year-old Josie Lou Ratley near Deerfield Beach Middle School.
Jurors reached the decision after about four hours of deliberations.
Ratley, who was stomped in the head, underwent multiple surgeries to relieve pressure on her brain and spent more than 40 days in intensive care at a Broward County hospital after the assault.
The big question was whether the jury would believe Treacy, then 15, was not aware of his actions at the time of the assault.
Prosecutor Maria Schneider argued the defendant knew what he was doing and presented evidence that Treacy sought out Ratley and threatened to kill her.
"I'm satisfied because justice was done but this is another one of those cases where it's very difficult to be joyful under any circumstances," Schneider said, according to NBCMiami.com. "We have a young lady whose life will never be the same, will never be normal, and we have a young man who has some serious issues who clearly is facing a very very significant and serious sentence."
Treacy's defense attorney, Russell Williams, argued for support of a claim of insanity, saying Treacy was in a dissociative episode during the attack.
"Obviously I'm disappointed, I think a key piece of evidence didn't come into evidence, which was the video interrogation, and I'm hoping that on appeal the appellate court sees that and the conviction gets reversed and we do this again," Williams said, NBCMiami.com reported.
The video, Williams said, could shed more light on Treacy's troubled state of mind about two hours after the attack. Early in the video, Treacy calls himself a "monster" and says he could not remember committing the attack.
Williams said he plans to appeal the verdict.
Authorities say Ratley had sent Treacy text messages about the suicide of his brother.
The defense told jurors Treacy was treated for five months after seeing his brother's body hanging from a tree, and that the messages sent him into a state where he couldn't control his actions, the Sun-Sentinel reported.
"But you know what, again, there are millions and millions of people who experience horrific things, one horrific thing, and don’t go out and kill others," Schneider told jurors.
Experts on both sides agreed Treacy has PTSD. But prosecution psychiatrists testified that Treacy clearly knew right from wrong and understood the consequences of his actions.
Schneider said Treacy sent text messages to his friends saying he was going to kill the girl by snapping her neck and stomping on her skull. Treacy wrote out a will before the attack, the prosecutor said.
The Sun-Sentinel reported Treacy attacked Ratley at a bus stop near the school, knocking her to the ground, smashing her head on the concrete and stomping on her with steel-toe boots.
The assault ended when a teacher tackled him.
Kayla Manson, 13 at the time, was arrested for pointing Ratley out to Treacy. She will stand trail in August for being an accessory to attempted murder, The Associated Press reported.
Treacy has been held without bond since his arrest.
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