A key witness can not be called in defence of a detective sergeant accused of planting a sawn off shotgun on a north Donegal Travellers' encampment because he was in the witness protection scheme.
A jury at Letterkenny Circuit Court heard that he was placed in the scheme after he was named in a statement by a detective garda.
The trial heard the witness supplied information which helped prevent several dissident republican attacks in Northern Ireland in the 1990s.
Information from the witness was passed to Garda chiefs by Det Sgt John White, who has pleaded not guilty to possession of a firearm on 22 May 1998.
On the same night, Det Sgt White received information from his informant, which he passed on to Chief Supt (now Assistant Commissioner) Dermot Jennings at Garda HQ.
The information led to the interception of a 940lb car bomb on its way to a target in Northern Ireland the next day.
