The murder of 'Mr Moonlight' DJ Bobby Ryan was driven by the "oldest motive in the world - love and money", the Court of Appeal has heard.
On the third day of Patrick Quirke's appeal against his conviction for murder, the prosecution responded to claims that gardaí investigating the murder had an agenda and that Quirke was prejudiced by irrelevant evidence.
"In the circumstantial case, context is everything," barrister Michael Bowman said, in setting out why details about the relationship between Mary Lowry and Patrick Quirke was important evidence in the trial.
Mr Bowman disputed the defence argument that the "Dear Patricia" letter - a letter Quirke wrote to a newspaper agony aunt about the breakdown of his relationship with Ms Lowry - was enough to establish motive.
Mr Bowman said the "taking of the phone", a reference to Quirke taking Ms Lowry's mobile and texting Mr Ryan, was a "tremendous moment of consequence" that was not referenced in letter.
"Nor was the fact that he was deriving a revenue stream from Mary Lowry," said Mr Bowman.
"In Dear Patricia, he didn't detail the extent of the relationship at all."
In part of his submissions on Tuesday, Quirke's defence barrister Bernard Condon said his reason for seeking to limit the material put to the jury was so the case would not "degenerate into a family law dispute".
He said it was within the prosecution's gift to limit the chance of prejudice.
Mr Ryan (52) disappeared on the morning of June 3, 2011 after spending the night at his girlfriend Ms Lowry's home in Fawnagown, Co Tipperary.
Although married, Quirke had previously had an affair with Ms Lowry.
It was the prosecution's case that Quirke killed Mr Ryan and hid his body in a run-off tank on Ms Lowry's lands so he could rekindle the affair.
Quirke was said to have staged his discovery of the body two years later when his lease on the land was about to end.
The defence has claimed Quirke was subjected to "mocking" and "prurient" questioning in garda interviews, the transcripts of which should not have been put before a jury.
However, Mr Bowman said he wanted to be clear that there could be "no suggestion of the defendant being oppressed" during garda interviews.
He said Quirke had repeatedly presented himself for questioning on a voluntary basis.
"No one had an agenda," he added.
Mr Bowman said that after agreement with the defence, "quite a lot of material" had been taken out of the various garda interviews when they went before the trial jury.
"It wasn't the case of the prosecution being pig-headed and saying everything goes in," he said about the concessions that were made.
"We accommodated as best we could, and when we took a view in relation to something, we asked the judge to mitigate and the judge ruled.
"She was perfectly entitled to rule as she did."
In relation to a comment made by gardaí during an interview with Quirke, when it was put to him that he was "getting cash on demand and sex on demand" from Ms Lowry, Mr Bowman said the prosecution case had been made clear.
"Inevitably, it was always the prosecution position that the motive here is, and I'm not saying sex and cash, but certainly the oldest motive in the world - love and money," he said.
Earlier, in concluding def-ence submissions, Mr Condon argued that the judge who issued a warrant for the search of Quirke's home was "kept in the dark" by gardaí over their intention to seize his computer.
A number of incriminating Google searches were found to have been made on the computer, including "rate of human decomposition" and "human body decomposition timeline".
Mr Condon said the search warrant was obtained by Detective Sergeant John Keane from Judge Elizabeth McGrath of the District Court on May 13, 2013, but was not executed until the morning of May 17.
The barrister said that during the trial, Superintendent Patrick O'Callaghan testified he had requested that Det Sgt Keane ensure computers be searched for at the Quirke home. However, no mention of computers was made in the search warrant, he said.
The appeal continues before Mr Justice George Birmingham, Ms Justice Isobel Kennedy and Mr Justice Patrick McCarthy.