EAST CAMBRIDGE, Mass. —"How to fake a mental illness."

Michael "Mucko" McDermott typed those words into an Internet search engine a year before he gunned down seven co-workers, he acknowledged Friday at his insanity defense murder trial.

But during a 90-minute grilling by the prosecution, the 43-year-old software programmer, who claims to be living under a religious delusion that his victims were Nazis and he is currently in purgatory, denied cooking up the story to avoid punishment.

McDermott

"You've studied how to fake mental illness," charged prosecutor Thomas O'Reilly, displaying on a large projection screen a print-out of the December 1999 search recovered from McDermott's computer files.

"That's correct," McDermott said.

"Now you are relying on your mental arsenal of knowledge of how to fake because this is just one big game to you, isn't it," O'Reilly said.

"Of course, not," McDermott shot back.

McDermott faces seven counts of murder and life in prison for the Dec. 26, 2000, killings at Edgewater Technologies, an Internet company in Wakefield, a suburb of Boston. Prosecutors contend McDermott plotted the rampage in revenge after Edgewater officials told him they planned to garnish his wages to pay his $5,500 IRS debt.

But the defense maintains that McDermott suffers from schizophrenia and to this day had no understanding of what he did to his office mates.

As with his direct examination Thursday, McDermott's testimony was a mix of the bizarre and banal. He matter-of-factly described the Archangel Michael, whose appearance McDermott claims triggered the massacre, as a winged man with brown hair: "He was shorter than I which disturbed me."

And in the same voice insisted that he was in limbo rather than East Cambridge: "This is not a court."

But moments later, he admitted fighting with other inmates, which he termed "constructs," about what to watch on the jail television. He said it was essential for him to wear his long, wild hair down to keep voices out of his mind, but acknowledged putting his hair in a ponytail during meals to keep it clean.

McDermott said he had heard voices for at least 14 years, but pressed by O'Reilly, he said he could not remember ever telling anyone, not his sister, not his best friend, not even his wife, about his delusions.

"You didn't start telling people about these voices until after you were charged with seven counts of murder, isn't that true?" asked O'Reilly.

"No, it's not," McDermott said.

During the trial, McDermott has stared at a Bible, seemingly paying no attention to the courtroom procedures, but cross-examined by O'Reilly, he became impatient and at times confrontational.

When the prosecutor insisted he answer a series of questions with either a "yes" or a "no," McDermott huffed, "As much as you are trying to make every question black or white, yes or no, lots of them are gray."

He said he had avoided telling therapists and psychiatrists about the voices because he believed he would lose his job if he confided in them. He said he tried to appear normal to mental health workers by researching insanity on the Internet and in a book entitled "Clinical Assessment of Malingering and Deception."

"I searched for 'faking sanity' and nothing came up," he said.

The psychiatrist who treated McDermott for six years leading up to the shootings also testified Friday. Dr. Alan Rothman said he diagnosed McDermott with major depression, obsessive compulsive disorder and mixed character disorder. Rothman said he prescribed sleeping pills and Prozac for McDermott. He said he never mentioned hallucinations nor delusions.

But a psychologist who counseled McDermott following a 1987 suicide attempt said he mentioned hearing ringing and noises from televisions that were turned off.

"He told me, 'You learn not to talk to him or people think you're crazy,'" Ann Schwab testified. "He often referred to himself as paranoid."

Heather Neuswanger, former co-worker of McDermott's

Jurors also heard from one of McDermott's closest friends. Heather Neuswanger, who met McDermott when they worked at Duracell Batteries, described him as "gentle and kind and bright and funny and very inquisitive."

She said she and McDermott had a falling out six months before the shooting over unspecified issues of "trust," but that she visited him in jail. He was the same as ever, she said.