A police chief has insisted further errors uncovered in a review of a controversial scheme to deal with fugitive republicans will not have the same dramatic consequences as the mistake that collapsed the trial of an IRA bomb suspect.
The review by Lady Justice Hallett, which was ordered after Co Donegal man John Downey was wrongly given a government assurance he was not wanted by UK police even though he was being sought over the 1982 Hyde Park bombing, identified two other cases where similar errors were apparently made.
Northern Ireland's Chief Constable George Hamilton said it was "highly unlikely" the two other assurance letters sent in error would lead to the collapse of future court cases.
Lady Justice Hallett was asked by Prime Minister David Cameron to examine the administrative process agreed between the last Labour government and Sinn Fein for dealing with so-called 'on-the-runs' (OTRs).
Her report findings published today, which have been accepted by the Government in full, found "systematic flaws" in the operation of the "unprecedented" scheme but concluded it was not unlawful in principle.
Acknowledging a "catastrophic" error had been made in the Downey case, she insisted the letters of assurance did not amount to amnesties.
The senior judge said while the scheme was not well publicised, and effectively kept "below the radar", it was not secret.
"The administrative scheme did not amount to an amnesty," she said.
"Suspected terrorists were not handed a 'get out of jail free card'."
Stormont First Minister Peter Robinson, who at one point threatened to resign over the issue, claiming the scheme was a secret side deal that effectively issued amnesties, said the report's findings confirmed his view the process as "wrong in principle and shambolic in practice".
He called on Northern Ireland Secretary Theresa Villiers to act to ensure no one could use the letters in the future to avoid questioning or prosecution.
But Sinn Fein's Gerry Kelly said Lady Justice Hallett's conclusions showed that allegations of amnesties and get of jail free cards were just a "unionist myth".
In her final paragraph, the judge urged all sides not to make "political capital" out of her findings.
"However the scheme is characterised, I have found nothing which, to the mind of this independent observer, should be allowed to undermine the peace process in Northern Ireland," she said.
Under the scheme, which started running in 2000, almost 190 republicans who had left the UK jurisdiction received assurances they were not being sought by British authorities. A number who applied for assurances were not granted them because they were considered as wanted.
The process saw names of individuals passed to the Government, the majority through Sinn Fein. The names were then handed to police and prosecutors to assess their status. A report on each individual was sent back to the Government and, if they were declared as not being wanted, a letter of assurance was then issued to the individuals.
The probe by Lady Justice Hallett was ordered in the wake of the high-profile collapse of the case against Mr Downey, who was accused of murdering four soldiers in the IRA's Hyde Park bombing in 1982.
The prosecution of the 62-year-old was halted at the Old Bailey in February after Mr Justice Sweeney found he had been wrongly sent one of the Government's letters of assurance in 2007 when in fact the Metropolitan Police were looking for him. Police in Northern Ireland were blamed for not flagging this up in its report on Downey sent to the Northern Ireland Office (NIO).
Justice Sweeney decided Mr Downey's arrest, when he travelled through Gatwick airport last year, and the subsequent prosecution had therefore represented an abuse of process. Mr Downey denied involvement in the attack.
Household Cavalry Lieutenant Anthony "Denis" Daly, 23, died in the explosion in Hyde Park on July 20, 1982 alongside Trooper Simon Tipper, 19, Lance Corporal Jeffrey Young, 19, and 36-year-old Squadron Quartermaster Corporal Roy Bright.
While Northern Ireland police were criticised over the error, the court proceedings also shone a light on the wider administrative scheme of sending assurance letters to on-the-runs.
In her review, Lady Justice Hallett outlined details of the two other cases where letters were sent in error:
:: The use of an incorrect date of birth to search a police database may have missed an offence potentially linked to an individual. An individual with the same name and same year of birth was wanted for a terrorist offence. It has not yet been established if this was the same individual who received the letter of assurance.
:: An individual who was wanted for an offence committed after the 1998 Good Friday peace accord was sent a letter with a general assurance they were not wanted. The origin of the mistake lay in the fact the police believed they were only searching for pre-1998 offences and therefore did not outline details of the 2003 offence when informing the Northern Ireland Office that the individual was "not wanted by the PSNI".
Responding to the report, Mr Hamilton said he accepted Lady Justice Hallett's findings and apologised to the Hyde Park victims.
He said the two further errors highlighted in the report were being "managed".
"The difference though between those is that those errors have been identified and we have taken action around those so that even with those two additional errors mitigation is in place," he said.
The chief constable added: "If they ever were to come to court it is highly unlikely that an abuse of process application (to collapse the case) would be successful as it was in the Downey case because we have identified the mistake and we have done something about it."
He noted Lady Justice Hallett described the police's actions in the Downey case as lacking logical explanation.
"That is not the case of those two further administrative errors; the consequences of those are being managed," he said.
The police are reviewing all the OTR cases they considered as part of the process - an exercise that could take years.
The Government accepted the report's conclusions and recommendations.
Outlining the findings to Parliament, Ms Villiers said: "I know that recent events have revived painful memories for those affected by that terrible atrocity (Hyde Park) and I apologise again on behalf of this Government for any hurt that has caused."
She added: "I fully accept the Hallett Report's conclusions and recommendations and am determined that the Government will act on them.
"But, as I have said before, as far as this Government is concerned, the OTR scheme is over."
Key findings of the 273-page report included:
:: Lady Justice Hallett said there was no logical explanation for why police in Northern Ireland failed to flag up that Mr Downey was wanted by the Metropolitan Police in London.
:: She also criticised the fact that the PSNI missed at least two further opportunities to rectify the error.
:: She found that the Government did not widely publicise the scheme but that it was not secret. But she said the lack of openness caused particular distress to victims of terrorism.
:: There was insufficient legal consultation as to the consequences of sending the on-the-run letters.
:: There was pressure exerted by Sinn Fein on the Government to quickly resolve the OTR issue and subsequently by Government on officials, but that pressure "did not cross the line" into becoming improper.
:: The scheme lacked proper lines of responsibility, accountability and safeguards.
:: There was insufficient liaison with other police forces and senior prosecutors elsewhere in the UK.
:: A total of 13 convicted OTRs benefited from royal pardons.
The Downey case triggered a political crisis at Stormont earlier this year.
Many politicians, particularly unionists, reacted furiously, claiming they knew nothing about the letters.
Mr Robinson only withdrew his resignation threat when Mr Cameron ordered the review.
A police commander subsequently claimed that 95 of those who received letters were linked, though only by intelligence, to 295 murders during the Troubles.
Sinn Fein accused its political rivals of manufacturing the crisis and claimed information about the process was already in the public domain before the Downey case.
It also downplayed the significance of the letters, rejecting the claim that they amounted to amnesties and insisting they were merely a statement of fact about an individual's status at a point in time.
In her conclusion, Lady Justice Hallett urged politicians to consider the victims.
"One catastrophic mistake has been made and it cannot be undone," she said.
"The families of those killed in the Hyde Park bombing have no choice but to come to terms with that fact, as devastating as I know it has been for them. Other mistakes have been made and need correcting.
"But this can be done in a measured and proportionate way. No one should use my findings to make political capital. Those whose lives have been devastated by terrorism deserve better. They have suffered enough."
The Northern Ireland Affairs Committee at Westminster is conducting a separate inquiry into the OTR controversy.
Asked later if the Government intended to "rescind" all the letters that had been sent, Ms Villiers said: "Rescind sort of suggests that they have some kind of statutory status so it is not really the best way to describe how you deal with a factual statement.
"But, whatever you want to call it, I have pledged very clearly today at the despatch box that, where errors are made, they will be corrected and I will take whatever action is required to do that.
"Before I do, I will need to take the advice of police and prosecutors and the Justice Minister."
The Northern Ireland Secretary said the process of seeking legal advice on the way forward had already begun.
She added: "I have had endless discussions of this issue ever since the Downey case collapsed.
"In part we were waiting for the review's conclusions so now we will be working in detail on the way forward.
"One of the reasons it is not wise to set that out in black and white just at the moment is because a hasty response, there is a danger you could end up saying something which jeopardised a trial rather than helped it."
Ms Villiers said the names of the OTRs would not be published because to do so "could potentially make it much more difficult to mount a successful prosecution".
"In addition to the legal and data protection issues there is a sound prosecutorial reason not to," she said.