Remy Farrell also said some jurors might think his client should be locked up, irrespective of whether he was guilty or innocent.
But he urged them to put such thoughts to the back of their minds.
Mr Farrell, in his closing speech on the 41st day of the Central Criminal Court trial, also suggested to jurors if they were to acquit Mr Dwyer, they “will be doing the unpopular thing”.
Earlier, prosecutor Seán Guerin, who on Thursday had commenced his closing argument, described the 42-year-old architect as “a sadistic and brutal pervert with nothing on his mind other than murder”.
Mr Dwyer is charged with murdering Dublin woman Elaine O’Hara at Killakee, Rathfarnham, Dublin, on August 22, 2012. Hours earlier, the childcare worker had been discharged from a mental health hospital.
The accused pleaded not guilty to murdering the 36-year-old.
Mr Farrell, meanwhile, read from a document found on his client’s hard drive entitled Killing Darci — in which the accused said he had fantasised about killing since he was a teenager, about deciding who lived or died like God, his hero.
He said the trial had “sex, lots of it, kinky sex, a middle-class professional — the kind of technical and forensic evidence you’d expect from an episode of CSI, evidence that has placed the participants, Graham Dwyer and Elaine O’Hara, under the spotlight”. He said jurors had a mountain to climb to simply apply the presumption of innocence.
Mr Farrell claimed on every occasion the defence had sought to raise the possibility of suicidal ideation, the prosecution had sought to dispute it, and establish she essentially “skipped out the hospital door that day”.
He said there was quite a remarkable degree of cherry picking by the prosecution.
Mr Justice Tony Hunt will begin charging the jury on Monday.
However, before they left for the weekend, the judge told them the accused had been exposed to them in a very harsh light, and he advised jurors not to discuss the case over the weekend.
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READ MORE: Graham Dwyer trial: An acquittal would be ‘unpopular’, jury told