The murderous collusion at heart of Ulster's dirty war

The key finding of the Stevens report is its stark conclusion that security forces colluded in at least two murders, those of the solicitor Pat Finucane and a teenage student, Adam Lambert.

With this unvarnished statement, Sir John Stevens takes the theory of intelligence involvement in the Finucane killing and others out of the arena of allegation and into the realm of practical policing.

He declared: "I have uncovered enough evidence to lead me to believe that the murders of Patrick Finucane and Brian Adam Lambert could have been prevented. I also believe that the RUC investigation of Patrick Finucane's murder should have resulted in the early arrest and detection of his killers."

Sir John, who is now Commissioner of the Metropolitan Police, said evidence of collusion lay in the wilful failure to keep records, the absence of accountability, the withholding of intelligence and evidence, and through to the extreme of agents being involved in murder.

He added: "These serious acts and omissions have meant that people have been killed or seriously injured. The unlawful involvement of agents in murder implies that the security forces sanction killings."

Although the short public statement he issued yesterday concentrated on the Finucane and Lambert deaths, it is known that many more killings are dealt with in the full report. This is not being published.

Sir John pointed the finger at the RUC Special Branch and, in particular, at the Force Research Unit, a branch of Army intelligence, which he suspected had become deeply involved in lethal illegalities.

He concentrated on the FRU, interviewing 20 former members and preparing legal files on nine of them. A file on its former head, Brigadier Gordon Kerr, is among those which have been sent to the Northern Ireland Director of Public Prosecutions.

Echoing a previous police investigator, John Stalker, Sir John stated baldly that he was obstructed during his collusion inquiries: "This obstruction was cultural in its nature and widespread within parts of the Army and the RUC."

He said he had unearthed the late Brian Nelson, who was an Army agent within the loyalist Ulster Defence Association, only through his own team's efforts.

He added: "When he was interviewed I discovered that he had been in possession of an 'intelligence dump'. This had been seized by his FRU handlers when my first inquiry had begun, in September 1989. This crucial evidence had been concealed from my inquiry team."

As he moved in to arrest Nelson, information was leaked to loyalist paramilitaries and the press and the operation had to be aborted, with Nelson advised by FRU handlers to leave home.

In a more extreme act of obstruction, Sir John's office near Belfast was destroyed by fire as he again prepared to arrest Nelson. He says: "This incident ... has never been adequately investigated and I believe it was a deliberate act of arson."

He further complained that key documents were withheld for years by the Army and Ministry of Defence. He said that last November he had received for the first time additional documentation from the MoD, giving rise to several new and major lines of inquiry. Noting this "with considerable disquiet", he warned: "I am investigating if the concealment of documents and information was sanctioned and if so at what levels of the organisations holding them."

In a damning section of the report, Sir John accused the RUC of not treating Catholics thought to be at risk on a par with Protestants, saying: "Nationalists were known to be targeted but were not properly warned or protected."

He summed up: "The co- ordination, dissemination and sharing of intelligence were poor. Informants and agents were allowed to operate without effective control and to participate in terrorist crimes. Crucial information was withheld from senior investigating officers"

The Commissioner highlighted the activities of William Stobie, a member of the UDA who has since been shot dead by that organisation, who was a Special Branch informer.

Stobie was involved in the 1987 murder of Adam Lambert, a Protestant student mistakenly believed by the UDA to be a Catholic. Sir John said Stobie was arrested after the murder but was released without charge and became a Special Branch informer.

As the UDA quartermaster of the West Belfast Brigade, Stobie had been involved in storing and supplying weapons, the Commissioner said. His activities while an agent, "clearly indicated his central role in the commission of serious offences".

Sir John said it had been established that before the Finucane killing Stobie had supplied information that a murder was being planned. Afterwards he gave significant information about a firearm being collected. He went on: "This vital information did not reach the original murder inquiry team and remains ... under investigation by my inquiry team."

The Stevens team questioned three of the original suspects for the Finucane murder, as well as nine other men. It has been unable to bring charges but, according to Sir John, his investigation is continuing.

He said his team had also investigated an allegation that senior RUC officers briefed a Home Office minister, Douglas Hogg, that some solicitors were unduly sympathetic to the IRA cause. Mr Hogg controversially repeated this view in the Commons, weeks before the Finucane attack. Sir John said of these comments: "To the extent that they were based on information passed by the RUC, they were not justifiable and the inquiry concludes that the minister was compromised."

Sir John recommended a review of all police procedures into terrorist offences, retraining Special Branch officers, and agreements among all departments and agencies to ensure clarity of roles.

ANATOMY OF AN INQUIRY

14 years to complete

10,400 documents with a total of 1m pages and weighing more than 4 tonnes have been examined

15,000 people have been nterviewed

16,194 exhibits taken

3,000 pages in report

144 arrests made, with a total 94 convictions