A 65-year-old Wicklow farmer with dementia and Parkinson's disease has been deemed unfit to stand trial for the murder of his older brother in 2010.

Cecil Tomkins is charged with murdering 66-year-old Walter Tomkins at their home in Cronlea, Shillelagh on 1 July of that year.

When his case was called before the Central Criminal Court yesterday, Mr Justice Paul Carney heard there was an issue about his fitness to stand trial.

His barrister, John O'Kelly SC, said his client had been suffering from advanced and aggressive Parkinson's disease for a number of years and was currently an inpatient in Bloomfield Hospital in Dublin.

He said Mr Tomkins also had depression and dementia, lacked the capacity to make any decision and was unable to direct his solicitor.

He handed the court a report prepared by an interdisciplinary team and called a consultant psychiatrist from Bloomfield Hospital to give evidence on the issue.

Dr John Tobin said that Mr Tomkins had advanced dementia and very advanced Parkinson's disease, the latter since 2006.

"It's been very, very progressive," he explained.

The doctor also said that Mr Tomkins had a history of seizures secondary to loss of brain tissue.

"His ability to communicate is very restricted. I hear the word 'yes' from him no-matter what I say," he testified.

"The charge he faces weighs heavily on him. The man is undoubtedly tortured," he added.

Dr Tobin said that his patient required total nursing care and was one of the most high-demand patients for his nursing team.

"He would not be able to instruct counsel or a solicitor. He would not be able to follow what was going on in a court room," he added.

He said that Mr Tomkins was cognitively impaired and that he was disorientated in place and time.

"At times, he doesn't know where he is or recognise people," he explained.

"The brain is so impaired that small changes make the dementia more severe. He goes in and out of delirium," he added.

He said that his treatment was now palliative care, repeating on a number of occasions that it was 'very sad'.

Dr Tobin concluded that, arising out of his diagnosis of advanced Parkinson's disease with dementia, Mr Tomkins was unable for the judicial process.

"He's unfit to stand trial," he said.

Dominic McGinn SC, prosecuting, said he did not disagree with the defence on the issue.

Mr Justice Paul Carney said that the evidence had overwhelmingly proved that the accused came within the applicable section of the Criminal Law Insanity Act. He directed that the proceedings be adjourned until further order.