REVELATIONS that security services have withheld intelligence in high profile court cases in Northern Ireland is nothing new.
In 2006 the Omagh bomb families raised concerns that MI5 had deliberately withheld intelligence, including phone intercepts of the bomb team, from the police investigation into the murders of their loved ones.
Sir Hugh Orde claimed MI5 had not withheld intelligence that was ``relevant or would have progressed’’ the police investigation.
The then Chief Constable’s qualified statement reportedly failed to satisfy the campaign for an investigation into the security services’ actions surrounding the Omagh Bomb investigation.
In March 2010, MPs on the Northern Ireland Affairs Committee in the House of Commons questioned whether the Omagh bombing could have been stopped had action had been taken against dissidents suspected of having carried out previous attacks.
The Government refused MPs’ demands for a definitive statement on whether security agencies had identified those thought to have carried out the attack in the immediate aftermath and if so why they were not arrested.
The MPs also challenged the Government’s claim that the decision to withhold telephone intercepts of the alleged bombers from the original murder investigation, had been in the ``best interests’’ of national security.
Other cases in the past 10 years have also highlighted the withholding of intelligence.
In January 2000 the Ministry of Defence admitted it had destroyed two rifles used by the Parachute Regiment during the shooting dead of 14 unarmed civilians in Derry city in January 1972. It did so despite explicit instructions they should be secured for forensic examination by the Bloody Sunday Tribunal.
The Defence Secretary at the time, Geoff Hoon, insisted the guns’ destruction was down to human error and was not part of a criminal conspiracy.
It later emerged the British army had begun to destroy 14 of the 29 army rifles just three days before then Prime Minister Tony Blair had been due to announce a public inquiry into Bloody Sunday.
In 2003 one of Northern Ireland’s most senior forensic scientists Ann Irwin told a Belfast court police tried to pressurise her into carrying out forensic tests on evidence they knew might already be contaminated.
Mrs Irwin, who was testifying at the trial of Co Tyrone man Noel Abernathy for the attempted murder of two policemen, claimed police failed to follow proper procedures while collecting evidence at the scene of the shooting.
She said they then tried to “retrieve” the situation by asking her to carry out tests for firearms’ residue on the suspect’s clothes, despite the possibility they may have already been contaminated.
She told the court: "They (the police) tried to retrieve the situation by asking the lab to compromise its science.”
The forensic scientist said she had refused their requests because she could not have stood over the results.
She further alleged that senior officers had tried to interfere with the work of forensic scientists over a number of years in an effort to cover up police mistakes in a range of criminal cases.
Mr Abernethy was subsequently cleared of all charges.
Trial judge Lord Justice Nicholson said he was “disturbed” by Mrs Irwin’s evidence.
The Police Ombudsman was asked to investigate Mrs Irwin’s claims.
While the PSNI was later cleared of any wrongdoing, the ombudsman raised concerns over the way in which police had collected evidence in the case.
In December 2003 bomb charges against two Co Down men were dropped after it emerged a PSNI detective had asked a forensic scientist to “modify” his findings to protect an informer.
Martin Brogan and Mark Carroll had been charged with possession of an explosive device after they were arrested near Newry in September 2002.
As the pair were due to go on trial their solicitors uncovered a letter from a forensic scientist who claimed he had been asked by a detective chief inspector to “modify” evidence he was due to give and omit “a number of sections”.
The scientist claimed the detective provided a copy of the original statement with the areas he wanted modified clearly marked.
The result, he claimed, would have been that the report would have omitted any reference to traces of explosives found on a third man, believed to have been an informer. Defence solicitors also found a memo written by another forensic scientist which stated that soldiers had contaminated evidence in the case by “opening bags in the exhibits room . . . and rubbing a gloved hand over the surface of the contents, in this case items of clothing”.
In October 1995 the weapon used to murder solicitor Pat Finucane was removed from Seapark Forensic Laboratories in Carrickfergus without authority and handed back to the British army.
At the time the gun was not only a crucial part in the investigation into Mr Finucane’s murder, but was also key to Sir John Stevens’ inquiry into security force collusion with loyalist paramilitaries.
The weapon had been found to be in perfect working order in 1992 when it first entered the forensic laboratory.
However almost as soon as it was handed back to the British army, a decision was taken to replace the barrel and slide of the pistol, destroying vital forensic evidence in any subsequent murder investigation.
In April 2003 Sir John Stevens, whose investigation into security force collusion in Northern Ireland lasted nearly 15 years, confirmed his detectives had been unable to identify who in authority had given permission for the gun to be wiped of its forensic history.
In December 2007 the trial of Omagh bomb suspect Sean Hoey heard that another explosive device may have been “forensically altered” by unknown individuals after black tape mysteriously appeared on its outer casing after it had been sent for forensic analysis in England.
Trial judge Mr Justice Weir described the tape’s appearance as “Houdini-like”.
In January 2004 four Co Tyrone men were cleared of an attempted rocket attack on a police station in Coalisland after it emerged during the trial that police investigating the case had not been told of the involvement of undercover soldiers in the planned operation against the dissidents.
Raising concerns that the involvement of undercover soldiers had been deliberately withheld during the case, the trial judge said:
``Even when the investigating officer became aware of the involvement of those soldiers, no attempt was made by the police to interview them and the soldiers declined to be interviewed by the defendants.
``The police, therefore, conducted a deliberately limited investigation focusing narrowly on the proximity of the first three defendants to the rocket launcher and avoided investigation of the wider circumstances leading to their presence at the location.
``The result was, it was argued, that the police and therefore the prosecution had effectively withheld from the court evidence of all the relevant events to the prejudice of the defendants.’’