The former Minister for Justice Alan Shatter has won his High Court appeal against a decision not to quash parts of the Guerin report examining the handling of claims made by a garda whistleblower.

In his ruling, President of the Court of Appeal Mr Justice Sean Ryan said in his view Mr Guerin was obliged to observe the rules of natural justice and of letting the other side be heard.    

He said there was a breach of Mr Shatter's rights because of the defective procedure that was adopted.

Mr Justice Ryan also said Mr Guerin was working under pressure dealing with such a large amount of documentary material under severe time constraint.  

He said Mr Guerin was in error, but the judge said he was very far from being personally critical of him in the overall context of what he had to do.

The matter will come back before the Court of Appeal later this month to decide what orders or declarations the court should make.

The report criticised Mr Shatter's handling of allegations of Garda misconduct in the Cavan/Monaghan division.

He resigned as a result, but was cleared of any wrongdoing by the O'Higgins report published in May.

The O’Higgins commission concluded that Mr McCabe had “acted out of genuine and legitimate concerns” but that many of his allegations were either unfounded or overstated.

He then took an appeal against the Guerin's findings, arguing he had suffered an injustice and his good name had been damaged.

Mr Shatter has welcomed the judgment delivered by the Court of Appeal today.

In a statement this afternoon, he says the successful outcome is a huge relief to him.

He says the findings and conclusions of the report did enormous damage to his good name and reputation and cost him his position as Justice Minister and his Dáil seat.

The statement also goes on to thank the judges of the Court of Appeal, his legal team, his family and close friends.

Earlier this year, Mr Shatter asked Taoiseach Enda Kenny to withdraw the state's legal defence in his case over the Guerin report.

“The conclusions of the O’Higgins commission totally contradict and are incompatible with the adverse findings made against me in the Guerin report,” he said.

“I believe it is in the public interest, following on from the O’Higgins report, that these proceedings be rightly resolved without the necessity for a further contested court hearing,” he said.