Raymond White is the sort of person whom republicans and some commentators like to describe as a "securocrat"; as if, by the act of labelling him in this way, they can discredit and discount anything that he has to say.
Life isn't that simple. White, a former RUC assistant chief constable who was in charge of both Special Branch and CID (Criminal Investigation Department), is a complex man who is emerging as one of the most significant witnesses and articulate guides to the recent troubles. Last Monday, on BBC's Panorama, he was the only former police and intelligence officer willing to put his head above the parapet to talk to John Ware about the Omagh bombing.
He opened a can of worms by discussing that British intelligence agencies in monitoring mobile phones in the Irish Republic. He and Ware raised worrying questions about whether Government Communications Headquarters (GCHQ), Britain's electronic eavesdropping agency, did all it could to prevent and solve the Omagh bombing of August 1998.
One of the minor surprises on Panorma was seeing White appear on the same side as Nuala O'Loan, the former Police Ombudsman with whom he is more usually at loggerheads. Both were critical of British intelligence agencies for allegedly not passing on all they knew; meaning that police investigating the atrocity were working with one arm tied behind their backs.
In her report on Omagh, O'Loan criticised White and Sir Ronnie Flanagan for "poor leadership" of the police during the investigation. Last year, White was named under parliamentary privilege by Mark Durkan, the SDLP leader, as one of three officers who allegedly failed to co-operate fully with O'Loan's Operation Ballast report into the murder of Raymond McCord Junior in a row over drugs involving Mark Haddock, a rogue informer in North Belfast UVF. White, and the two other officers, were later exonerated of wrong doing by Paul Goggins, an NIO minister.
White said that he offered to respond to written questions from the Ombudsman but was not willing to enter into a free ranging discussion with her detectives without having adbance notice of the questions. He has a law degree himself and was acting on legal advice, which will always be to prepare carefully for an interview with the investigators and to know the details of what is to be discussed.
Later White maintained that MI5, which lay outside the Ombudsman's purview, controlled of the budget for informants and set intelligence requirements.
It played a key role in deciding whether a difficult agent like Haddock should be arrested and charged or kept in play for his intelligence value. There was, as Haddock's police handler Trevor McIlwrath pointed out to me at the time, a flow of intelligence from Haddock about planned attacks in the republic and on Sinn Féin premises.
This may have led the MI5 paymasters to conclude that he should not be arrested. Once cautioned he was unlikely to admit anything and that there would have been little chance of a successful prosecution. With hindsight they may have got it wrong, but it wasn't an easy or uncomplicated calculation.
What would have happened if there had been a UVF bomb south of the border and it emerged that an informant in the unit which planted it, a man who warned of previous attacks, had been paid off because he was suspected of ordering a drugs murder from jail? There might have been questions to answer.
There might also have been calls for an inquiry if the agent had been charged with offences of which he was not convicted and which he later claimed were a fit up to prevent him continuing to give warnings on planned cross border attacks.
There are no easy answers in this murky world where violent and dishonest men work as law enforcement agents, only life and death decisions made under pressure in real time.
McIlwrath, who recruited Haddock, wanted him arrested, but was over ruled. He suffered a nervous breakdown for which he is still receiving treatment as a result of the pressure of regularly debriefing a man he suspected of being involved in several murders. Yet he knew that Haddock had handed him at least one bomb which Special Branch had been able to disable.
As a more senior officer, White had a clearer overview. He had worked on the interface between intelligence services and the police. He was head of Special Branch, the detective unit which was charged with gathering pre-emptive intelligence to prevent attacks, in Belfast until 1989. He then took over command of all policing operations in Belfast and later moved on to become head of the Criminal Investigation Department (CID). He was put in charge of both CID and Special Branch in 2001.
"People have a simplistic view that the intelligence services existed to provide good old CID with information to put people before the court, but that is not always how it worked" he told me last week. "The Security Service's remit is far in excess of that. It produced political intelligence as well as everything else and in my experience that was sacrosanct, even paramount over prosecutions. Prosecutions were a product but not the only product, keeping your intelligence base was generally the priority."
On Panorama, White confirmed that Special Branch had identified a cell phone used in the Omagh bombing and passed it to GCHQ for monitoring. Based in Cheltenham, GCHQ had a listening post in Capenhurst, Cheshire, monitoring the republic's telephone communications with the rest of the world, and another in Armagh which covered cross border traffic.
Garda sources have indicated that the Eircell mobile phone was identified in a Real IRA attack on Newry some months before but it's number was never passed to them by the RUC. This decision is hard to justify because the bombs planted in Northern Ireland were generally made in the republic. Instead of calling on the gardai, Special Branch asked GCHQ to monitor the phone.
Panorama found that it was used in a failed bomb attack in Banbridge where the code word "the bricks are in the wall" was used to signal that the bomb was in place. The same code word was used in Omagh but was missed by GCHQ monitors. If they had been listening live and reacted appropriately, O'Loan has pointed out, road blocks could have been set up to intercept the bombers.
Panorama claimed that even after the atrocity, details were withheld from CID and Gardai who spent nine months analysing 6.4 million mobile phone calls to get the same information. In the hours following the bombing, when RIRA was in chaos, gardai could have carried out searches with a good chance of finding evidence. As it was their raids came months later when the trail was cold.
Why would GCHQ have held back on sharing the product of their intercepts in the wake of such an atrocity? Shaun Woodward, the Northern Ireland Secretary of State, doesn't believe they did; however. But the British prime minister has ordered a review of GCHQ's role in Omagh.
Did the intelligence services and GCHQ have some secret interest that took precedence over even the Omagh investigation? On this most sensitive point, White is more willing to pose questions than provide answers.
"If GCHQ are capable of doing this with targets who are resident in the south of Ireland, just how far does their monitoring capacity extend? Does it extend to the Gardai? Does it extend to monitoring Irish government communications?"
These questions deserve answers.