Graham Dwyer's lawyers say there is an expectation in the media and in bar rooms that the jury should go with their gut and convict the architect, but it is vital the jury remember their client retains the presumption of innocence.

Both the prosecution and defence summed up their case in the trial of the 42 year old of Kerrymount Close, Foxrock who denies killing Elaine O'Hara in August 2012.

The prosecution has described Graham Dwyer as a 'sadistic and brutal pervert with nothing on his mind other than murder'.

Mr Dwyer, a 42-year-old architect from Kerrymount Close, Foxrock, denies killing Elaine O'Hara at Killakee mountain in Dublin in August 2012.

The prosecution has argued that Graham Dwyer devised an elaborate plan to stab Elaine O'Hara to death without getting caught by making it appear like a suicide.

They said he did this to realise a deep-rooted sexual fantasy to kill a woman during sex.

They said untraceable phones, the remote location and the manipulation of a vulnerable person like the childcare worker was all part of that plot.

In his final address to the jury Sean Guerin, leading the prosecution, said the architect revealed this intent in text messages sent to Elaine O'Hara.

He said the accused did not anticipate the recovery of these messages, particularly from two phones thrown into the Vartry reservoir.

The prosecution asked the jury to discount suicide as an option, saying its inconceivable and at odds with Elaine O'Hara's psychiatric reports and her plans for the future, including her excitement about volunteering at the Tall Ships festival.

Mr Guerin says Graham Dwyer can be connected beginning, middle and end to the disappearance of Ms O'Hara, and he described him as a sadistic and brutal pervert with nothing but murder on his mind.

The defence has asked the jury to question whether these messages are fantasy or reality.

Defence counsel Remy Farrell conceded that a rape and stabbing fantasy called 'Killing darci' found on a hard drive at the architect's home was authored by Graham Dwyer.

They say the forensic evidence is out of kilter with the prosecution's case and point to the fact that an analysis of the 36 year old's skeletal remains found at Killakee mountain revealed no foul play.

He said the jury may regard the evidence and his client as repellent - he said the events we are dealing with can't be characterised as even close to normal. But he also said it is vital the jury remember this his client enjoys the presumption of innocence.

Mr Justice Tony Hunt will charge the jury on Monday before sending them out to deliberate on a verdict.

Originally posted at 7.31am