AUGUSTA – The defense attorney for John A. Okie said the defendant in a double-slaying case “was crazy” the day of the first killing and delusional at the time of the second, but a prosecutor told jurors Monday that the 22-year-old defendant was bluffing.

Assistant Attorney General Andrew Benson said Okie was stabilized at the time of the killings and most likely faked his diagnosed psychosis after beating and stabbing his sometime-girlfriend at her home in Wayne and then stabbing his father six days later in Newcastle.

The first victim, Alexandra “Aleigh” Mills, fell down a flight of stairs during an argument with Okie before he beat her with a wooden banister and stabbed her repeatedly in the neck and head on July 10, 2007. Benson said her throat was slashed almost ear-to-ear.

John S. Okie, 59, was stabbed during a “rip-roaring argument,” between father and son in their home, said Benson. He said the younger Okie plunged a knife into his father, “disemboweling him.”

Okie, wearing a light blue shirt and tan pants, his blond hair neatly combed, sat quietly and expressionless during Benson’s statement, which took about an hour. The trial in Kennebec Superior Court is expected to last about two weeks.

Jurors also may consider a manslaughter charge against Okie, and must consider whether he suffered from mental disease or defect at the time of the killings, Justice Joseph Jabar told them. Okie, who’s using an insanity defense, has pleaded not guilty.

Benson acknowledged that Okie had suffered bouts of mental illness in the past. But in summer 2007, “Mr. Okie was perfectly stabilized,” said the prosecutor. While a psychologist for the defendant later found Okie to be psychotic, a separate psychological review concluded that there was a 98 percent chance Okie was feigning his mental illness, Benson said.

Okie’s attorney, Peter DeTroy, went into great detail to convince jurors that Okie – whom he repeatedly referred to as Johnny – is profoundly mentally ill.

He presented a timeline showing how Okie’s mental state deteriorated from early 2004, with time spent in and out of schools, mental health facilities and on medication. He told jurors his client suffered from schizophrenia, marked by delusions and paranoia.

At one point, Okie barricaded himself in his room and called police, telling them that his mother, Karen Okie, had raped him and was trying to addict him to heroin, DeTroy said.

“Johnny Okie is a very, very sick young man,” the attorney said. While schizophrenia does not improve, its symptoms can be controlled. That was compromised, he said, when Okie neglected to take his medication and sometimes “self-medicated” with alcohol and marijuana.

On the day he killed Mills, Okie “was more and more delusional” and believed he had to kill her, DeTroy said.

“He was crazy,” said DeTroy, adding that Okie arrived at her Wayne home with no weapon and no plan. After the slaying, he left in his car, only to return to get gasoline from a can in the Millses’ garage because he was afraid of running out.

Nearly a week later, Okie got into an argument with the second victim and, believing that his father was trying to poison him, attacked and killed him, said DeTroy.

The state’s lead witness, Timothy Mills of Wayne, described the grisly scene he encountered when he found the body of his daughter, whom he and his wife had adopted when she was 2 months old.

Mills described her as a gifted basketball player who had a magnetic personality and attended the University of Maine at Augusta after graduating from the private Kents Hill School in Readfield in June 2006. He said John Okie had been a guest at the Mills home on several occasions.

Okie has been held without bail since he was arrested hours after his father’s body was found.