Lawyers for the man who calls himself Clark Rockefeller began their defense in his kidnapping trial Wednesday with the testimony of a forensic psychologist who said he is "completely deluded" and not responsible for his actions.

The psychologist, Catherine Howe, said the defendant has "delusional disorder, grandiose type" and "narcissistic personality disorder." She said those mental illnesses impaired his ability to recognize the wrongfulness of his conduct last July, when he took his 7-year-old daughter, Reigh, during a supervised visit in Boston. They were found in Baltimore six days later; the girl was unharmed.

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• Partial List of Witnesses at the 'Clark Rockefeller' Trial

The defense claims that Rockefeller, whose real name is Christian Karl Gerhartsreiter, was legally insane when he shoved a social worker who was overseeing the visit and fled with the girl.

Prosecutors say Gerhartsreiter is a German-born con man, a consummate liar who concocted incredible stories about himself to work his way into wealthy circles in New York, Boston and Los Angeles. They say he was perfectly sane when he took his daughter after losing custody of the girl to his ex-wife.

Howe said Gerhartsreiter has severe symptoms of narcissistic personality disorder, including a grandiose sense of self-importance, a sense of entitlement and arrogant or haughty behavior. She said his narcissism worsened as more and more people believed the fantastic stories he told about himself to the point where they became delusions.

"The data points to the fact that at some point, his grandiosity, his narcissism ... became so intense that his world, his reality, was not the reality that everybody else would have seen," Howe said.

Assistant District Attorney David Deakin questioned her diagnoses, at one point listing various aliases and personas he has allegedly used since moving to the United States from Germany in 1978, including Dr. Reiter, a cardiovascular surgeon from Las Vegas, and Charles "Chip" Smith, a ship's captain based in Chile.

Howe acknowledged that not all of his identities were delusions, but said that his 16-year use of the Rockefeller name "became a delusional belief."

Deakin asked Howe about a report she wrote for the defense in March, when she referred to Gerhartsreiter as a "diagnosis unto himself."

He then held up the Diagnostic and Statistical Manual of Mental Disorders, a guidebook published by the American Psychiatric Association that provides criteria for diagnosing mental disorders.

"There's no diagnosis in here for liar, is there?" he asked.

Howe said the book does contain a diagnosis for malingering, or faking, symptoms of mental illness.

When asked again by Deakin if the book contained a diagnosis for a liar, she replied, "There's nothing in there under that word, no."

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