28-year-old Brian Rattigan of Cooley Rd, Drimnagh has denied the murder of 21-year-old Declan Gavin of Mourne Rd, Drimnagh, in August 2001.
The prosecution claims Mr Rattigan stabbed Mr Gavin in a targeted attack at a fast food outlet in Crumlin Shopping Centre.
The State is relying on fingerprint evidence to prove Brian Rattigan was the killer.
However, defence lawyers said the prosecution had failed to forensically link the print to the death of Declan Gavin.
In his charge to the jury this morning Mr Justice Barry White said the State was relying on circumstantial evidence.
He told the jury it could not be influenced by the fact that many witnesses in the trial suffered from memory loss or failure in the witness box.
He said no adverse inferences should be drawn against the accused man from this, nor could the jury speculate on what answers the prosecution might have anticipated from such witnesses.
The issue for the jury he said was 'who did it?', and, in particular, 'was it Brian Rattigan?'
The jury was told that the state maintains that the palm print found on the window of the Abrakebabra shop puts Brian Rattigan at the scene.
This, coupled with the fact that he lied to gardaí about his whereabouts and the fact that his friend's car, the same make as the one used by the perpetrator, was found burned out hours after the killing, made it clear he was the killer.
However, the defence says 17 other fingerprints were also found at the scene and none of these was identified.
Defence barristers also pointed out that Brian Rattigan was not the sole suspect in the case as 33 other people were arrested in connection with the killing.
They say the finger print evidence has been significantly undermined and did not forensically link Brian Rattigan to the killing.
