Letters telling nearly 200 members of the IRA, including Sinn Féin’s John Downey, that they were not wanted for prosecution were not “an infringement of the rule of law”,

British attorney general Dominic Grieve told the Commons yesterday.

Earlier, British prime minister David Cameron said he completely understood “the depth of anger and concern” in the UK following a London court’s decision last week that Mr Downey should not be tried for the 1982 Hyde Park bombing in which four soldiers died.

The court ruling came after it emerged that Mr Downey had received a letter in 2007 from the Northern Ireland Office telling him he did not face prosecution for any offences committed during the Troubles.

Convicted paramilitaries were released under the terms of the Belfast Agreement but so-called on-the-runs (OTRs) - suspects who had not been convicted of offences - like Mr Downey were left in an uncertain position.

Sinn Fein campaigned strongly for them to be guaranteed immunity from prosecution, and it emerged in last week’s court case that nearly 200 subsequently received written assurances from the British government that they would not be prosecuted.

Despite demands that the court ruling be appealed, Mr Grieve said he and the British Crown Prosecution Service had ruled it out because they "do not consider that it gives rise to any prospect of a successful appeal". Rejecting the argument that the rule of law had been undermined by Mr Justice Sweeney's ruling last week, Mr Grieve said it actually upheld its principles "because it emphasises the fairness at the heart of our criminal justice system" – even if he did not like the result.

Over an hour
The fury about the decision to grant so-called letters of comfort gave Northern Ireland a rare place at the head of MPs' concerns, and the attorney general was questioned for over an hour.

Mr Grieve was repeatedly forced to deny that the previous Labour government had given terrorists an amnesty, saying people had letters declaring that they were not facing prosecution on a particular date, but could be prosecuted if new evidence emerged.

“[It] was not, and never could be, an amnesty. That might have been what the previous government sought at one time, but an amnesty could be achieved only through legislation, and no such legislation was put through the house.”

The Commons anger was shared by a succession of SDLP MPs, including former leader Mark Durkan, who said the last Labour government had blighted "the peace process with their penchant for side deals, pseudo-deals, sub-deals, shabby deals and secret deals".

Do deals
Defending his decisions in office, former Labour secretary of state Peter Hain infuriated Democratic Unionist MPs by saying that Labour had had to "do deals" with the DUP, but also with Sinn Féin, to get "the negotiations to succeed"

In 2005 Mr Hain published legislation that would have enabled OTRs to qualify for an exemption certificate which would ensure they would not be prosecuted for crimes. However, he had to withdraw it after a year-long battle with Conservatives and unionists, though Sinn Féin later also opposed it when it realised that British soldiers could equally benefit from it.

Thirty-eight members of the IRA have been given letters stating they are not wanted for prosecution since control over justice and policing was devolved to Stormont four years ago, Mr Grieve told MPs. The London court ruling was delivered last Friday and made public this week.