Gary Campion, who is being represented by Madden & Finucane, begins his appeals against two murder convictions at the Court of Criminal Appeal, Dublin.

Gary Campion has moved to appeal separate convictions for the murders in Limerick of bouncer Brian Fitzgerald outside his home and Frank Ryan who was shot dead by a passenger in his car while driving.

Campion (31), last of Limerick, had denied being involved in the murder of Mr Fitzgerald (34) at Corbally on November 29 2002 and had also denied murdering Frank Ryan (21) on September 16 2006.

He was found guilty in two separate Central Criminal Court trials and was given two life sentences, first by Mr Justice Peter Charleton on November 15 2007 and then by Mr Justice Paul Carney on May 28 2009.

Counsel for Campion, Martin O’Rourke SC, submitted to the Court of Appeal today that the trial for the murder of Mr Fitzgerald should not have been allowed to proceed because the defence weren’t in a position to have a key prosecution witness psychologically or psychiatrically examined.

Convicted murderer James Martin Cahill was the primary witness against Campion in the Fitzgerald trial, Mr O’Rourke said, and the case “depended entirely” on his evidence.

Medical notes found evidence of Cahill’s paranoia and hallucinations, Mr O’Rourke said. Cahill had complained that he was hearing voices which had “talked to him about things he had done” and “gave him instructions from time to time”.

When inconsistencies were put to Cahill, he repeatedly fell back into explaining them away by saying “he had heard voices etc,” Mr O’Rourke said.

An appropriate medical examination would have confirmed or alternatively may have excluded any disorder Cahill had and that would have allowed the defence to approach the case on a firm footing.

It seems the witness’ evidence was purely “whimsical” Mr O’Rourke said. At one stage, John Dundon disappears from his account, the gun evidence changes and on another day he might say something different about another person.

One cannot rely on anything this witness said, Mr O’Rourke said. A provisional assessment had found Cahill to be suffering from psychopathy but he needed to be examined further to find out.

That was why a medical examination was necessary and proceeding without one rendered the trial unfair. It was a matter on which the jury were entitled to medical assistance, Mr O’Rourke said.

The appeal continues today before President of the Court of Appeal Mr Justice Seán Ryan, Mr Justice Garrett Sheehan and Mr Justice George Birmingham.

Sunday World