Nick Clegg has announced a new independent legal inquiry into the 1994 Mull of Kintyre chinook disaster that killed 29 people, including top intelligence and anti-terrorist officers.
The deputy prime minister said the evidence surrounding the crash en route from Northern Ireland to western Scotland, which the RAF initially blamed on the two pilots, would be reviewed by a senior lawyer with no connections to previous reports.
The RAF board of inquiry ruled that the pilots – flight lieutenants Jonathan Tapper and Richard Cook – were guilty of "gross negligence". Their families have since been fighting to clear their names.
Clegg made the announcement in the House of Commons during Prime Minister's Questions as he was filling in for David Cameron who has flown to France to be with his ill father.
He told the Commons that the legal figure heading up the new investigation would have no links to past inquiries into the Mull of Kintyre accident.
"I am pleased to be able to confirm today we will be holding an independent review of the evidence of the Mull of Kintyre disaster, and I hope a review will be welcome by those who died in this tragic accident," Clegg said.
"To ensure its complete independence, the review will be conducted by a respected lawyer who is independent of the government and who has not previously expressed a view on the disaster. The reviewer and the precise terms of reference will be announced soon."
In June 1994, the Chinook helicopter crashed into a hillside near the Mull of Kintyre lighthouse in thick fog.
Those on board, including top RUC special branch officers and a number of MI5 operatives, were on their way from Northern Ireland to a secret conference in Inverness.
Top of the agenda at that meeting was a discussion on the possible loyalist paramilitary response to the forthcoming IRA ceasefire, which came two months later.
Among those killed was the deputy head of RUC special branch, Brian Fitzsimmons, and senior anti-terrorist officer Supt Ian Phoenix who had helped co-ordinate with the police and SAS the killing of seven top IRA men at Loughgall, Co Armagh in 1987. As well their immediate families, among those who fought from the outset to clear the pilot's of any blame was Phoenix's widow Susan.
Five years after the crash the government faced calls for a fresh inquiry when Computer Weekly magazine released evidence claiming to cast doubt on the reliability of the helicopter's engine control software, supporting campaigners' claims that the aircraft was at fault and not the pilots.
In February 2002 a House of Lords committee rejected the RAF's verdict and found that there were no grounds for blaming the pilots.
© Guardian