They went to London in hope more than expectation. The family of Pat Finucane never supported this review of evidence by a “lawyer with strong links to the Conservative Party”, demanding instead the public inquiry they were initially promised by Tony Blair.

They leave with the personal apology of a Prime Minister for the “collusion” of British agents in Pat’s murder. But not, they say, the truth.

Mr Finucane’s wife Geraldine was in the House of Commons chamber to hear David Cameron say he was “deeply sorry” after the findings of the Da Silva report were made public today. But, ultimately, she was there to hear him refuse the public inquiry she believes her family needs and deserves.

“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. Most of all, most hurtful and insulting of all, this report is not the truth,” she told reporters afterwards.

She said the family wanted to be in the Commons to hear the words from Mr Cameron’s own lips. “We could have watched it on a television screen at home but we felt that was important. We felt that, after all this time, we needed to be there,” she told the Independent.

The sombre mood in the chamber this afternoon matched the occasion: a British government denied any “over-arching state conspiracy” but admitted to the collusion of agents of the state in the murder. “It was measured, rather than being raucous. [The Commons] can often come across very rowdy on television but this was not the occasion for that,” said Mrs Finucane.

Appearing before reporters dressed all in red, she said this latest report into her husband’s murder at the hands of Loyalist paramilitaries in 1989 was the result of a “process in which we have had no input; we have seen no documents nor heard any witnesses”. In short, she said, the family has had no opportunity to see the evidence for themselves.

“We are expected to take the word of the man appointed by the British government,” she said.

Flanked by her sons Michael and John and her brother-in-law Martin Finucane, she added: “Despite all these misgivings, we have tried our best to keep an open mind until we have read and considered the final report. We came to London with the faint hope that, for once, we would be proved wrong. I regret to say that, once again, we have been proved right.

“At every turn, it is clear that this report has done exactly what was required: to give the benefit of the doubt to the state, its cabinet and ministers, to the Army, to the intelligence services, to itself.

“At every turn, dead witnesses have been blamed and defunct agencies found wanting. Serving personnel and active state departments appear to have been excused. 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.

Michael Finucane, dressed - like his brother and his uncle – in a dark suit and tie, said that the public inquiry the family seeks has been promised to them by Ed Miliband, if he becomes Prime Minister. The refusal to grant one by successive governments, he said, was because the British state “has the most to hide”.

He said he accepted the use of the word ‘collusion’ in the report, as opposed to the stronger accusation of conspiracy because the former more accurately encapsulated “not just the deliberate acts of people who decide to do something, but also a culture that encourages and fosters them”.

After leaving the Houses of Parliament this afternoon, Mrs Finucane said she would welcome David Cameron’s apology and accepted it. “After all”, she said, “he is a human being”. But she added: “unfortunately he is quite removed from Northern Ireland or what went on in the late ‘80s. So maybe it isn’t very hard for him to apologise.

“I will give him the benefit of the doubt and accept the apology but it doesn't go far enough because I don’t really know what he is apologising for.”