Former secretary of state for Northern Ireland Peter Hain has said it is risible for key politicians to claim they had no knowledge so-called comfort letters were sent to IRA on-the-runs.

In a week when controversy over the scheme threatened to pull down Stormont’s devolved government, the Labour MP said it was clear for anyone who wanted to see that the assurances were not get out of jail cards, immunity or amnesty.

The political crisis was sparked when the trial of John Downey for the 1982 Hyde Park bomb spectacularly collapsed last week in London.

He had wrongly been told by the Police Service of Northern Ireland (PSNI) that he was not wanted for questioning or prosecution in the UK despite a Metropolitan Police warrant for his arrest for the murders of soldiers.

The case revealed the extent of an assurance scheme for OTRs and a deal the last Labour government struck with Sinn Féin that saw more than 180 individuals given letters similar to Mr Downey’s, clearing their way to return home.

Another five cases involving IRA terror suspects are active.

Writing a first-hand account in the Sunday Telegraph of how the scheme came about, Mr Hain suggested that if a line was to be drawn on Northern Ireland’s past it must include the pursuit of paratroopers involved in Bloody Sunday.

“There is no suggestion that the contents of the letters to those ‘on the runs’ were cleared with key politicians of all parties, or the details of the scheme shared, but the idea that they did not know anything about them is risible,” Mr Hain said.

“Even when the letters were in the public domain, there was still misrepresentation, whether wilfully or not, about what the letters sent between 2001 and 2012 actually said and meant — and this process caused the victims even greater pain.”

Mr Hain said no-one in government has anything to hide and ministers acted honourably.

“Diverting police time to investigate Bloody Sunday soldiers or crimes from the Troubles seems a waste when the priority today should surely be tracking down the tiny, but dangerous, attacks from dissident IRA groups, as well as facilitating ordinary, plain community safety,” he said.

Mr Downey (62), a Sinn Féin member and former oyster farmer who denies planting the Hyde Park bomb, returned home to Co Donegal where a planned homecoming party last night was cancelled. “Some elements of the media are portraying the event as triumphalist and insulting to bereaved families. That was never what it was about,” he said.

After Mr Downey walked free, First Minister Peter Robinson warned he would resign unless an inquiry was launched and letters to OTRs rescinded. A judge is examining the entire issue but the letters remain in place.

Mr Hain outlined the background to the arrangement in 2007.

Sinn Féin's Gerry Kelly gave names of OTRs to the Government but ministers were not told who the individuals were. The PSNI checked records for evidence which could lead to an arrest or prosecution at the time or into the future and after a second check the Northern Ireland Office (NIO) signed the letters.

The Attorney General confirmed the scheme was lawful, Mr Hain said.

While the majority of the cases were dealt with under the last government, almost 40 outstanding applications were taken on by the coalition Government when it assumed power in 2010.

Sinn Féin president Gerry Adams claimed the entire controversy around OTRs was a sham crisis.

“It is important to understand that the letters provided cannot be rescinded. If you’re not wanted — you’re not wanted,” he said. “Clearly, despite all of the feigned brouhaha and hot air generated by unionist leaders this process is not an amnesty.”

Deputy First Minister Martin McGuinness claims the fact other republicans were denied letters - and told they would be arrested if they entered the UK - proves that assurances were nothing more than official confirmation that there was no evidence linking individuals to offences..

Nationalist politicians in Northern Ireland also claimed unionists have been aware of the scheme for a long time — noting references to it in a number of public forums, reports and publications in recent years.

Meanwhile, DUP leader Mr Robinson has accused former prime minister Tony Blair of a "deliberate deception by omission" by failing to tell the majority of politicians in Northern Ireland about the agreement his government struck with Sinn Fein.

The crisis at Stormont compounded difficulties party leaders have had agreeing on stalled proposals for dealing with outstanding peace process issues, including the toxic legacy of the past, drawn up by former US diplomat Dr Richard Haass.

Sinn Féin was not the only group to seek information on named individuals.

According to the judgment in the Downey case, an NIO briefing note from September 2002 recorded 162 names provided by Sinn Féin - 61 of whom were told they could return.

The document also stated that the Irish Government sought information on two people and the Prison Service information on 10.

The Department of Justice in Dublin clarified that it did not issue any letters to any individuals in respect of OTR issues.

PA