MR Brendan O'Donnell wrote a letter to Hitler while he was at the Central Mental Hospital in Dublin, the Central Criminal Court has been told.
Dr Brian McCaffrey, a clinical psychiatrist, said yesterday he had no doubt Mr O'Donnell was insane.
He agreed with Mr Kevin Haugh SC, prosecuting, that Mr O'Donnell had written a letter to Hitler in June 1995. Mr O'Donnell had talked "a lot of nonsense" to him (witness) at that time, such as that he met Hitler in Killarney and wanted to kill the Pope.
Dr McCaffrey said there was a mixture of madness and a crude attempt by Mr O'Donnell to portray himself as being more mad than he actually was. It was his view Mr O'Donnell was a malingering madman rather than a malingering sane man. It was "very dangerous" to believe Mr O'Donnell was malingering when he had an illness.
Mr Haugh put it to the witness that Mr O'Donnell was antisocial, had a blood lust, liked killing, covered his tracks, calculated the odds and functioned as a thinking and not as an irrational person. But Dr McCaffrey said he had "no doubt this fellow is definitely insane".
He was being cross-examined on the 39th day of the trial of Mr O'Donnell (21), a native of Co Clare, on 12 charges relating to events in the west of Ireland in 1994
Mr O'Donnell has denied the murder of Ms Imelda Riney (29) and her son Liam (3) between April 28th and May 8th 1994. He also denied the murder of Father Joseph Walsh (37), former curate of Eyrecourt, Co Galway, between May 3rd and 8th, 1994, and the false imprisonment of Father Walsh.
He has pleaded not guilty to kidnapping Ms Fiona Sampson and Mr Edward Cleary on May 7th 1994 and to hijacking vehicles driven by both persons. He has also denied having a shotgun and ammunition with intent to endanger life and for unlawful purposes on the same date.
In court yesterday, Dr McCaffrey agreed Mr O'Donnell had given answers that fitted his own defence during his five-day testimony. It was his view that Mr O'Donnell's concept of the world was different from a normal person's.
Mr Haugh put it to the witness that a mentally ill person who did not think they were doing anything wrong in killing three victims would not try to cover their tracks. Mr O'Donnell had done that, he said, and had told sophisticated lies to gardai.
A mentally ill person, said the witness, might or might not wish to cover their tracks. He said Mr O'Donnell would know at a certain level about his mission to kill and would be anxious to succeed and not get caught.
He disagreed with a theory that Mr O'Donnell might have been sexually interested in Ms Imelda Riney and drove away with her from her home for sexual purposes.
Re-examined by Mr Patrick MacEntee SC, defending, Dr McCaffrey said schizophrenics and psychotics were capable of purposeful activity, telling lies and manipulation. He said he had no doubt Mr O'Donnell had a serious mental illness.
Dr Graham Turrall, a clinical psychologist practising in Toronto, Canada, said he carried out 30 different psychological tests on Mr O'Donnell in July 1995 and in January and March 1996.
He had also met Mr O'Donnell's grandmother and sister and had studied medical and other notes from the various hospitals and institutions in Ireland and England where Mr O'Donnell had been assessed from the age of four.
He had read a report from a psychologist who described Mr O'Donnell at 14 as a severely disturbed child. Another psychologist had suggested Mr O'Donnell was "extremely disturbed" and possibly had a delayed grief reaction to his mother's death but "much more worrying" was his "obsession" with guns.
Dr Turrall said he had studied a report from 1988 in which Dr Charles Smith said there were features in Mr O'Donnell which suggested he was "very close to psychosis if not already there".
He said Dr Smith had assessed Mr O'Donnell in May 1994 and believed he did not suffer from a major mental illness. Another psychiatrist, Dr Brian McCaffrey, had concluded Mr O'Donnell was mentally ill.
He said medical notes from prisons where Mr O'Donnell had been held in England from March 1993 to March 1994 showed concern about Mr O'Donnell's mental state.
Dr Turrall said Mr O'Donnell had considerable difficulties with the psychological tests and could not complete some. In the intelligence tests, it emerged that 99 per cent of the people of his own age were above his level of intelligence. The result would give him a mental age of an eight- to 10-year- old. The results of tests regarding academic achievement indicated he was at the same level as a seven-year-old.
Other tests were suggestive of brain dysfunction in the frontal lobe area, Dr Turrall said. The results of personality tests were consistent with a person exhibiting a severe depressed mood and were consistent with an antisocial, borderline personality.
He concluded from tests carried out on Mr O'Donnell last January that the result was consistent with a major mental illness.
The trial continues today