As a retired detective superintendent and former deputy head of CID in Belfast, the past few months have had a particular resonance for me as I closely followed the determined work by the PSNI – with the attendant widespread publicity – as they pursued the investigation into the murder of Jean McConville in 1972.
I was at the coalface of anti-terror policing during the whole of the Troubles and, in spite of the passing of the years, the horrors I witnessed are never far from the forefront of my mind.
But the recent concentration on the murder of this most unfortunate woman and the orphaning of her family of 10 has served to bring many of these atrocities into even sharper focus.
Thankfully, there is now a whole generation of younger people in Northern Ireland who know little of what it was like to have lived through the Troubles and the depths of depravity which were plumbed by our fellow man in the name of Irish patriotism, or loyalty to the Crown.
Overall, 3,500 people died as a result of the Troubles and 700 of these deaths occurred in north Belfast, where I served mostly as a detective. Quite remarkably, about half of these killings were solved.
Some of our politicians frequently hark back to those days and claim that the RUC was a bigoted force, but they conveniently ignore the fact that the prison population of convicted terrorists never seemed to vary much from 50% republican and 50% loyalist – hardly an indication of a one-sided force.
The solving of terrorist-related murders was never an easy task and it essentially revolved around making sense of all the evidence in a case, such as that from eyewitnesses, the results of the post-mortem examination, the forensic evidence and available intelligence.
As all of these elements were still fresh, an effective detective department could often act swiftly by making arrests and, hopefully, convictions would follow.
It would be an ideal world where all murders could be solved, but CID can no more achieve this than a surgeon can hope to save all his patients on the operating table.
In the case of Jean McConville, the PSNI had the lid of the case prised open for them by hearing first-hand accounts from some of those terrorists involved, who scored an own goal by recording their exploits for the Boston College Belfast project.
The developments in this case may give rise to optimism by many other families who lost loved ones, but I regret to say that I think these are forlorn hopes, due to the passing of so many years.
Many potential witnesses are now deceased, others are undoubtedly getting old, with subsequent memory loss. Important exhibits, which, with advances in forensic science, may now have been able to produce results undreamt of at the time, have been lost as the result of police stations being blown up.
Indeed, the forensic science laboratory itself, which contained so many exhibits, was almost totally destroyed by a huge IRA bomb in 1992.
Nonetheless, there is undoubtedly a large body of people out there who themselves were terrorists in their younger days and others who, while not necessarily terrorists, spontaneously became involved in someone's violent death.
So I firmly believe there is still a huge reservoir of information to be tapped into – if only we could find the right formula to allow it to flow in the direction of the PSNI and be acted upon.
It has often been repeated that there should be no hierarchy of victims, but looking back on my lengthy detective career, there are certain murders which I attended and, for some reason, retain a particular poignancy for me. Three of these occurred in the summer of 1972 – the worst year on record for sectarian killings.
I was in the last few months of my compulsory two years' probationary period as a uniformed constable before being accepted into CID.
I was on mobile patrol and, along with a colleague, I was the first officer on the scene of the murder of Paul Jobling, a 19-year-old Englishman, who was working on a youth project in the nationalist Moyard area of west Belfast. He had obviously fallen into the hands of a loyalist killer gang and was severely tortured before being shot.
Within weeks, we attended the scene of the murder of James Lindsay, a Protestant from the Shankill area, whose "offence" was to have a Catholic girlfriend. He had been savagely beaten to death.
The third victim was William Mathews, a Catholic from Divis Flats. He, too, had been tortured and beaten to death.
All three were found at the bottom of Glencairn Road and, due to the similarities in the way these murders were carried out, I have a reasonable suspicion that the same gang was responsible.
Another murder which haunts me is that of Private Gary Barlow, who was serving in the Lower Falls area in March 1973. He was part of a patrol which was dispatched to search premises in McDonnell Street and performed anti-sniper duty to protect his colleagues.
When the operation had been concluded, the patrol clambered back into their armoured vehicles, but, tragically, Pte Barlow was mistakenly left behind and a gang of local women soon assembled and cornered him in an alleyway until an IRA gunman arrived and shot him dead.
These horrific killings all occurred during the same era that Jean McConville was taken away and murdered. I have little doubt that many of those involved are still around.
Hopefully, they have a troubled conscience, which may persuade some of them to come forward and help bring justice to the surviving relatives of their victims.
Alan Simpson is the author of Duplicity and Deception (Brandon)