By Sandy Smith
BBC Panorama Editor
On Wednesday the Omagh families met Prime Minister Gordon Brown at Number 10 to discuss the outcome of an inquiry into Panorama's revelations that GCHQ were recording mobile phone exchanges between the Omagh bombers on the day of the attack.
The report by the Intelligence Services Commissioner Sir Peter Gibson had been ordered by Mr Brown and was published last month.
Panorama's September 2008 programme, "Omagh: What The Police Were Never Told", disclosed that GCHQ had monitored up to five mobile phones used by some members of the bomb gang during the 100 minute bomb run from the Irish Republic to Omagh, but that the detectives trying to identify the bombers were never told this, even though they were desperate for leads.
None of the perpetrators have been convicted of the bombing, which killed 29 people, two unborn babies and injured 250 people on 15 August 1998, despite promises from the-then Prime Minister Tony Blair that no stone would be left unturned in the hunt to bring the culprits to justice.
However, although appearing to confirm many aspects of the programme, Sir Peter avoided holding any branch of the intelligence services to account for the fact that the detectives were never told that intercepts existed and that the telephone numbers of some of the bombers were known.
Sir Peter also criticised Panorama for making "allegations" that the bombing could have been prevented.
In fact the programme made no such allegation. Rather, we asked whether the bombing could have been prevented - a question we now consider even more justified by Sir Peter's failure to challenge our central claim: that GCHQ was listening to the mobiles of some of the bombers while the bomb was being driven to Omagh.
The Northern Ireland Secretary Shaun Woodward told Parliament Sir Peter's review was "exhaustive" and "comprehensive".
Now Panorama publishes a detailed response to Sir Peter's criticisms of Panorama and highlights the many questions we say it fails to answer. Readers can judge for themselves whether they consider Mr Woodward's comments are merited.
Even to this day detectives have never been officially told about the phone monitoring.
The families say they want to know why neither Sir Peter nor the Northern Ireland Secretary have had anything to say about the GCHQ policy in place in 1998 that appears to have prevented even one telephone number being passed to detectives to get them going even though 29 people lay dead.
Sir Peter comments only on the "cautious way" Special Branch shared intelligence with the CID.
He just says it was not part of his remit to investigate the reasons for their "caution" but he "does not doubt" there were "good operational reasons" for it.
Sir Peter says the Branch could have asked GCHQ for "material that might have existed" to disseminate to the CID, but that "the record shows no such request was made".
The Omagh relatives consider this to be his single most extraordinary comment.
They ask if any reasonable person would seriously consider that the entire intelligence gathering apparatus of Northern Ireland would need to be specifically asked to collect intelligence to help identify those responsible for the single worst atrocity of the Northern Ireland conflict?
While Mr Woodward thinks Sir Peter's work was "exhaustive", some senior officers John Ware has spoken to beg to differ: "Gibson has surface skated" said one, adding that he had been "appointed to close the curtain on Omagh".
You can read Panorama's detailed response and make your own mind up.