A man accused of murdering his wife and cutting her head off told gardaí that he heard voices in his head that said "sometimes you have to behead somebody because this person is possessed".
Diego Costa Silva (35) also told gardaí that he had confessed to cheating on his wife and that he believed she was going to try to kill him.
He said he didn't feel safe and thought that if he didn't do it, "she could do it to me".
The Central Criminal Court jury hearing his trial has been told that they will be asked to return a "special verdict" under the Criminal Law (Insanity) Act 2006.
Mr Costa Silva (35) has pleaded not (NOT) guilty to the murder of Ms De Campos Silva (33) on November 4, 2021 at their home in Charlestown Place, Finglas.
Before he killed his wife, he said he had been in the Mater Hospital having been detained by gardaí after he was stopped while running in Dublin city centre in his bare feet and wearing only a pair of shorts.
When he was released from hospital, his wife picked him up and drove him home some time between 6pm and 8pm, he said.
At about 6am, he said he had a "fight" with his wife and he "wasn't feeling safe". He told the detectives he has "hurt on my mind, a sound or vibration in my ear and a voice in my head." He later complained of having "something electronic in my ear" and of hearing "so many voices".
He described his wife biting him on the leg and scratching his shoulder with her nails before he struck her on the head two or three times with a cup. He said he then began choking her before putting his foot on her neck. She fainted, he said, and he stabbed her "in her heart" before cutting off her head. He added: "I took her head, I took a knife and I cut her head."
When asked why, he said: "How can I explain? Sometimes you have to behead somebody because this person is possessed."
He described four knives that he used and said it took about 10 minutes to remove her head. He called gardaí 10 or 15 minutes later.
He said he had previously cheated on his wife and told her about it. She was upset and their relationship became strained, he said, but they stayed together.
He said he did not tell his wife about the voices and when asked if she knew there was something wrong, he said "she complained when I smoked weed". He said he last smoked three days previously and would smoke one or two joints a day, more if he could get it.
He said he does not take other drugs and his wife never smoked but would sometimes drink wine.
Detective Sergeant Louise McHugh told Mr Costelloe that following Mr Costa Silva's interviews, he was released from detention and she arrested him and charged him with his wife's murder. He did not reply. A urine analysis taken following his arrest was positive for cannabis but not for alcohol or other drugs.
Garda Colin Miley told Mr Costelloe that two days before the killing, he was on bike patrol at about 3.20pm when he saw Mr Costa Silva running barefoot, wearing only shorts on Middle Abbey Street in Dubiln city centre. Garda Miley caught up with Mr Costa Silva near the Spire on O'Connell St and found him to be distressed and disorientated, his eyes were bulging and he was sweating profusely.
The garda noted cuts and grazes to his feet and when asked what he was doing, Mr Costa Silva said he had jogged from Finglas to the city centre and he likes to jog barefoot. When asked if he was "okay", Mr Costa Silva said he was upset and depressed following an argument with his wife.
Garda Miley had concern regarding Mr Costa Silva's mental health and detained him under section 12 of the Mental Health Act to be examined by a doctor. Mr Costa Silva was taken to Store St Garda Station where he agreed to go to the Mater hospital to be assessed.
On the journey to the Mater, Garda Miley noted the accused was crying and seemed highly distressed. When a nurse asked if he was feeling suicidal, Mr Costa Silva replied: "Yes."
The trial continues in front of Mr Justice Michael MacGrath and a jury of seven men and five women.
