The Justice Minister has defended the a decision by the gardaí not to co-operate with an investigation by the Northern Ireland Police Ombudsman into a murder in Donegal eight years ago.

The Ombudsman is investigating the possible involvement of PSNI officers in the exposure and subsequent murder of Denis Donaldson in April 2006.

Mr. Donaldson was a former Sinn Féin politician and official. He was murdered less than a year after being exposed as a British spy.

In response to written Dáil questions, Minister Alan Shatter said the first responsibility of the gardaí was to investigate crimes within this jurisdiction.

He said the Police Ombudsman in the North had no authority over gardaí and that the hunt for the killers of Mr. Donaldson could be compromised by comments gardaí made to Northern authorities.