A GARDA sergeant found two knives in a file box in the basement of architect Graham Dwyer's workplace after he volunteered the information to gardai through his solicitor, the Central Criminal Court has heard.
Mr Dwyer (42), of Kerrymount Close, Foxrock, is pleading not guilty to the murder of Ms O’Hara (36) at Killakee, Rathfarnham on August 22, 2012.
Ms O’Hara, a childcare assistant from Killiney, was last seen alive near Shanganagh Cemetery in Shankill.
Her remains were found by a dog walker in undergrowth in the Dublin mountains on September 13, 2013.
The prosecution maintains Mr Dwyer killed her for his own sexual gratification.
Detective Sergeant Peter Woods told the jury he found a hunting knife and a flick knife in the basement in February 17 2014
Det Sgt Woods said on February in evidence he received a phone call from Mr Dwyer's solicitor Jonathan Dunphy and an accompanying fax message with a sketch map of the basement at A&D Wejchert Architects, Baggot Street Lower.
The fax was sent "on the initiative of Mr Dwyer and his solicitor" and not the gardai.
The map pointed to two magazine-holder style filing boxes on a top shelf in the basement.
"I found two knives, one larger than the other," Det Sgt Woods told Sean Guerin SC, prosecuting. "
One was a "Buck Special" hunting knife in a black leather scabbard and the smaller was a flick knife.
Both knives were held up in court by Det Sgt Woods for the jury to see.
Det Sgt Woods told the court that when the buck knife was found it was not in its original presentation box.
Gardai had purchased a replica of it before they located the knife so they were aware of its presentation, he added.
He said the knife cover they found was in “pretty good condition” with some small marks and scratches, and the knife itself in good clan condition.
The second knife was also in good condition and its safety catch in place, he added.
The court was told Mr Dwyer was charged on October 18th 2013 and the book of evidence served in January 2014.
Under cross examination, defence barrister Remy Farrell said it became apparent from the prosecution evidence that gardai had attached significance that a buck hunting knife had been ordered by the defendant.
Det Sgt Woods said the fact it was delivered on August 21, 2012, was “hugely significant” for investigators.
Mr Farrell said gardai were also concerned there was no sign of the knife, adding that Chief Superintendent Diarmuid O' Sullivan has made a “huge emphasis” on this.
The defence said it was this that the communication and sketch showing exactly where the knife was being stored was sent to gardai, he added.