LARGO — Diagnosed with schizophrenia, Benjamin Bishop thought he was Osama bin Laden and Adolf Hitler, sometimes talked to the TV, and believed gangs were after him.
These are among the delusions that public defender Christina Porrello listed Tuesday to the 12-member jury in the first-degree murder trial of Bishop, 20, charged with fatally shooting his mother, Imari Shibata, and her boyfriend, Kelley Allen, on Oct. 28, 2012.
Bishop, she said, is not guilty by reason of insanity.
"His mental health history is well-documented and shows that this is not something that was conjured up overnight," Porrello said. "He was legally insane at the time of this offense."
In opening statements, assistant state attorney Janet Hunter-Olney contended that the killings were premeditated and that Bishop knew that what he was doing was wrong because he called 911.
In his interview with detectives, Hunter-Olney added, Bishop told them that Shibata yelled at him and demanded he take his medications and get a job.
Bishop, then 18, went into his bedroom at the family's home at 205 Cedar Key Court in Oldsmar.
"He stewed," Hunter-Olney said. "During that three-hour period prior to the shootings, the plan was formulated to kill his mother."
In the early morning of Oct. 28, Bishop grabbed a 12-gauge shotgun he had been hiding from his family and walked to his mother's room, he told detectives. When she asked what he was doing, Bishop fired at her and Allen several times. Shibata, a nursing assistant, and Allen, a swim coach, died at the scene.
Bishop called 911.
"I just shot my parents," he told a dispatcher. "I think they are dead."
Witnesses called to testify this week will include detectives who will say Bishop showed no signs of confusion after the shooting and two experts who will testify that he is not legally insane, Hunter-Olney said. Defense attorneys will call two additional experts who concluded differently.
Porrello, the defense attorney, portrayed Bishop during opening statements as a troubled teenager with a lengthy history of mental illness.
Since 2011, Bishop was placed in protective custody under the state Baker Act and was shuffled between several facilities. Medical records detail the extent of his schizophrenic state, including Bishop's belief that his medications were going to kill him.
"Every single time I take this medication, my head gurgles and my heart gurgles," he told detectives. "I know my mother would continue to make me take the medications. I knew I would die."
He also showed up at Morton Plant Hospital twice in May 2012 because he thought he was having a heart attack. Both times, doctors determined he was not ill.
"This is not a mental illness," Porrello said, "that he had a choice over."
The trial is scheduled to resume today.
Contact Laura C. Morel at email@example.com. Follow @lauracmorel.