'Shocking levels of collusion by the State over lawyer's death'

The Prime Minister said sorry “on behalf of the Government and the whole country” for the “appalling crime” after an official inquiry concluded that Royal Ulster Constabulary police officers helped loyalist paramilitaries carry out the killing.

But in a statement to MPs, Mr Cameron said the report had found no evidence of an “over-arching conspiracy” involving the British state.

The murder victim’s widow Geraldine dismissed the inquiry report by Sir Desmond de Silva QC as “a sham...a whitewash...a confidence trick.”

Mr Finucane, 38, was gunned down in front of Geraldine and three of their children by paramilitaries from the Ulster Defence Association.

He was shot 14 times after the attackers confronted him while he ate Sunday lunch at his Belfast home.

The 500-page report yesterday concluded that police and security officials “furthered and facilitated” the killing.

It said security officials helped to make Mr Finucane a target by wrongly portraying him as an IRA sympathiser. One or more officers also suggested him as a potential target to UDA members.

The report also found RUC police officers failed to investigate the murder adequately. They failed to retrieve the gun used in the murder which had been passed to William Stobie, a Special Branch agent in the UDA.

Sir Desmond’s report also highlighted a series of failures in the handling of Army Intelligence Corps agent Brian Nelson, who infiltrated the UDA.

There were suspicions he was motivated by a desire to see Republicans killed and was prepared to withhold information from his handlers if he felt he was carrying out justifiable targeting.

But the report also found no evidence that Government ministers had any knowledge of Nelson’s activity or of the plan to kill Mr Finucane. Nelson died in 2003.

In his statement to MPs, Mr Cameron said: “It is really shocking this happened in our country. We do not defend our security forces or the many who have served in them with great distinction by trying to claim otherwise. Collusion should never, ever happen.” Matt Baggott, Chief Constable of the RUC’s replacement, the Police Service of Northern Ireland also apologised.

But Mrs Finucane, who was wounded in the attack, said: “Yet another British government has engineered a suppression of the truth.

“The dirt has been swept under the carpet without any serious attempt to lift the lid on what really happened to Pat and so many others.

“This report is a sham, this report is a whitewash, this report is a confidence trick dressed up as independent scrutiny and given invisible clothes of reliability.

“But most of all, most hurtful and insulting of all, this report is not the truth.”