The State has lost its appeal against a High Court decision that a former soldier should be awarded damages for a failure to diagnose and treat him for psychological injuries he sustained while in the Lebanon more than 30 years ago.

The Supreme Court ruled it was completely satisfied that the High Court's finding that the State had breached its duty of care to Victor Murtagh, of Ballymote in Sligo, by failing to diagnose and treat his post-traumatic stress disorder was amply supported by credible evidence.

However, it reduced the amount of damages awarded to Mr Murtagh from just over €300,000 to just over €150,000.

Mr Murtagh was 21-years-old and beginning his first tour of duty in the Lebanon in October 1986 when he was exposed to a number of dangerous and stressful incidents that traumatised him.

By the end of November he was unwell and was treated in hospital, but allowed to return to duty.

In the following months, two Irish soldiers were killed, including Corporal Dermot McLoughlin, who was also from Sligo and had befriended and supported Mr Murtagh.

The High Court heard it was known that Mr Murtagh was suffering more than most from the stressful events around him, and was showing clear signs of stress such as uncontrollable shaking and trembling.

It found his commanding officers should have been alerted to the fact that he was particularly susceptible to post-traumatic stress.

He was described as being a changed man when he came back to Ireland in April 1987.

He was difficult and irritable and had flashbacks and difficulty sleeping.

His marriage eventually broke down.

He was eventually diagnosed with post-traumatic stress disorder in 1996.

The court found there was a delay in the diagnosis and treatment of PTSD and that possibility was not investigated as quickly as it ought to have been, meaning Mr Murtagh continued to suffer and deteriorate.

The Supreme Court rejected the State's appeal against the High Court's finding on a number of grounds.  

However it found the award of damages made to Mr Murtagh was too high.

Outside court, Mr Murtagh said he was delighted the case was over as it had been going on for ten years.

His solicitor, Damien Tansey said his client was relieved.

He said he had gone to the Lebanon as a 21-year-old on one of the most dangerous missions ever undertaken by the Irish Army.

He said the case would have implications for others, as it imposed an obligation and duty on the State, and in particular on the Irish Army, to look after their personnel when they are sent to war zones.

He said it showed they must look after their people and if they suffered psychological injuries, the State had a duty of care to diagnose and treat them.

Mr Tansey said the fact that the case had taken so long to come to a conclusion, was a "classical example" of the bottleneck that existed in getting cases heard in the superior courts due to a shortage of judges.