Two psychiatrists have reached conflicting conclusions in relation to the mental state of a man who went on what was described as a rampage through Cork City and Cork Airport in May of last year.
38-year-old Edmond Stapleton's, defence is that he is not guilty by reason of insanity on 12 charges.
The charges include threatening to kill a garda and stealing his four-wheel drive, five counts of criminal damage and three counts of dangerous driving.
A psychiatrist called on Mr Stapleton's behalf believes he was insane at the time, while another doctor called by the prosecution has said he believes Mr Stapleton was suffering acute drug intoxication and was "out of his head".
Dr Paul O'Connell is a consultant forensic psychiatrist at the Central Mental Hospital in Dublin.
He gave evidence for the defence at the Circuit Criminal Court in Cork that Mr Stapleton was in a manic, psychotic state of mind when he assaulted and threatened to kill Traffic Corps garda Michael Bohane and stole his Toyota Landcruiser on Patrick Street in Cork City on 22 May 2011.
Mr Stapleton drove along pedestrianised streets and onto Cork Airport, crashed through the perimeter fence, and drove at two planes in a second four-wheel drive hi-jacked before he was eventually subdued.
Dr O'Connell told the court he believes Mr Stapleton was suffering from bipolar affective disorder and was insane at the time.
He added that Mr Stapleton's psychosis meant that he did not know what he was doing was wrong and neither could he refrain from his actions, meeting two of the criteria to be deemed insane at the time of the offences, under the 2006 Criminal Law Insanity Act.
The act specifically excludes intoxication by drugs or alcohol.
Challenged by prosecuting barrister Pearse Sreenan that Mr Stapleton's behaviour was consistent with someone taking various different drugs, Dr O'Connell replied that Mr Sreenan was looking for a black-or-white, all-or-nothing answer when the reality was more complex.
He said there was always a possibility that Mr Stapleton was suffering from a drug-induced psychosis, but he insisted that the clinical picture better fitted a conclusion of bipolar affective disorder.
He accepted that this could have been complicated by intoxication, but he said he did not believe Mr Stapleton's actions were due to intoxication on its own.
The court was told that Mr Stapleton tested positive for cannabis, cocaine, amphetamines, opiates and benzodiazepines in the days after his arrest.
Another consultant forensic psychiatrist at the Central Mental Hospital, Dr Damian Mohan, said he was absolutely certain that the incident happened because of drugs and that it would not have happened if Mr Stapleton had not been intoxicated.
He said he believed Mr Stapleton was "out of his head" at the time.
And he said the law was "black and white" in that it specifically excludes intoxication from insanity.
He said he was satisfied that Mr Stapleton's mental state at the time did not come within the terms of the 2006 Insanity Act.
Defence Senior Counsel Patrick McGrath put it to Dr Mohan that he had reached an "emphatically different conclusion" to his own colleague and that his conclusion also differed from the psychiatrist who treated Mr Stapleton at the Central Mental Hospital for seven months after these incidents.
Dr Mohan accepted that he was in the minority in relation to his conclusion.
