Murder accused Stephen Silver assaulted staff members of a psychiatric unit nine months before he shot Garda Colm Horkan 11 times, the Central Criminal Court has heard.
Dr Brenda Wright told Mr Silver's trial on Firday that the accused had been admitted to psychiatric units 17 times prior to the shooting, going back to 1997.
She detailed voluntary and involuntary admissions which, she said, occurred after Mr Silver had stopped taking his medication. His diagnoses included bipolar affective disorder and schizo-affective disorder.
On Thursday, Mr Silver told the trial that following his release from hospital in September 2019, he again stopped taking his medication. By the time he encountered Gda Horkan he said he had been feeling unwell for days and had been having confused thoughts.
Mr Silver (46), a motorbike mechanic from Aughavard, Foxford, Co Mayo, has pleaded not guilty to the murder of Det Gda Horkan knowing or being reckless as to whether he was a member of An Garda Síochána acting in accordance with his duty.
He pleaded guilty to manslaughter by reason of diminished responsibility, at Castlerea, Co Roscommon on June 17th, 2020.
'Extremely remorseful'
Dr Wright told defence counsel Roisin Lacey SC that she interviewed the accused three times in August and September 2020.
At the first interview, eight weeks after the shooting, she said Mr Silver was "extremely remorseful" but still believed that there had been "some conspiracy or threat planned towards him".
She said that "persecutory belief" was not evident in later reports when Mr Silver was assessed while in Mountjoy Prison.
By April 2021, after 10 months using antipsychotic medication, she said Mr Silver "was back to his normal self".
Mr Silver's history included bouts of grandiose delusions and psychotic episodes, the psychiatrist said, but there was also an eight-year period from 2010 when he appeared to be well, even though he was not taking medication.
In 2018, he was noted as having been "acutely psychotic" while at a motorbike rally.
When his urine was analysed, it showed the presence of PCP, an illicit drug which can lead to hallucinations and a "distortion in the sense of self or the environment", the witness said.
His diagnosis on that occasion was bipolar affective disorder, secondary to alcohol abuse and the use of illicit drugs.
In September the following year, Mr Silver went voluntarily to a local psychiatric unit after his family had become concerned about his "threatening", inappropriate and bizarre behaviour.
He told doctors he had not been getting enough sleep, had racing thoughts for four days, and had embarked on a "huge project building a shed for bike repairs".
On admission, he was threatening towards others and, although he had entered voluntarily, he left unannounced. When staff went to get him, he "physically assaulted" them but then agreed to come back to the unit, Dr Wright said.
His symptoms resolved quickly, she added, once he was given antipsychotic drugs. His diagnosis on that occasion was a manic episode of bipolar affective disorder.
Dr Wright will continue her evidence in front of Mr Justice Paul McDermott and a jury of seven men and five women on Tuesday.
