'Here's a decent man". So began a column in the London newspaper, the Irish Post in the issue of 26 November 1983. The columnist, Frank Dolan, was highly respected in the Irish community.

The subject of his column on that day was Billy Flynn, a private investigator who had taken up the cases of hundreds of immigrants short-changed by solicitors in the processing of wills in Ireland. The uneducated exiles had been easy pickings. Flynn doggedly pursued the matter. Eventually, he succeeded in getting the money back, winning praise from the likes of the Irish ambassador to Britain at the time, Noel Dorr.

Billy Flynn died suddenly last Sunday. To his large family, and legions of friends, his death is felt keenly, but what has been extinguished is more than a light in the lives of loved ones.

Flynn was a pain in the neck to the establishment, the institutions of state, many powerful elements in society. He patrolled the fringes of democracy, out there where the cracks appear and citizens are rendered victims.

Over the course of 30 years, the disaffected gathered at his door, unburdening themselves of injustices. Quite often his office was the last chance saloon for those who had exhausted all official avenues of redress. And quite often, they found what they were looking for.

It was to that office that Donegal publican Frank McBrearty and his wife Rosalynn came in early 1997. They were living through a nightmare created by nefarious elements in the gardaí. Flynn's better instincts told him not to get involved, but he was a sucker for hard luck stories.

His work broke the case, exposing the corruption which led to the Morris tribunal, and in turn the establishment of a modern, accountable police force. Judge Frederick Morris praised his pivotal role in the affair.

At various times, all institutions from the GAA, to numerous banks, to every arm of the state were subjected to his forensic skills. Currently, the Court of Criminal Appeal is deliberating on a 38-year-old manslaughter conviction, questions about which were raised following Flynn's investigations. In that case, as in many others, a distraught family showed up at his door, having despaired at the capacity of the state to right an injustice.

Don't for a minute remember him as an angel. His self-assessment in Gibgate, the book he penned about one of his cases, is illuminating.

"I am stubborn by nature and have a natural distrust of the establishment. I also loathe injustice. Especially when its victims are in no position to fight back. Don't get me wrong – I am no crusader. I entered this profession purely and simply to make money."

Gibgate told how Cork financier Finbarr Ross defrauded hundreds of pensioners through a Gibraltar-based company. It was withdrawn from shops after threats of a libel action from powerful individuals mentioned between the covers.

At the funeral mass on Wednesday, Gibgate was brought to the altar as one of the offertory gifts. Billy would have got a kick out of that. The House of God is a libel-free zone.

He was no Philip Marlowe, haunting dimly lit, mean streets. He rarely left home in rural Co Meath, preferring to direct operations, which included an insolvency practice, from his office therein.

The room spoke volumes about the man. A photograph of Pope John Paul II hung on one wall. A few feet away, there was a large portrait of the Magnificent Seven on horseback, led by Yul Brynner. Billy had a soft spot for some cowboys.

The centrepiece was a snooker table, littered with files of the various cases he was working on. He walked miles around that table. Typically, his left hand would have one of three phones pinned to an ear, the fingers of his right clasping a Rothman's cigarette. Somewhere within his orbit, there was always a hot drop of tea. When he wasn't on the blower, he was dictating his latest – often excoriating – missive to his daughter Jackie, who sat typing in the shadow of the smiling pontiff.

To say that his family was his rock would be to understate the relationship. Unlike many busy men, he provided emotional support as much as he relied on it. The eight children he and Eileen parented all lived as adults within 10 miles of the family home, some of them only a stone's throw away.

And his priorities in life were plain for all to see whenever one of his 22 grandchildren wandered in on a meeting. Irrespective of who was in attendance, barristers or distressed citizens, senior gardaí or strapped businessmen, the dynamic in the room changed. The matter at hand was relegated to an irrelevancy. The hardened PI suddenly melted into a mushy grandfather, focused only on the young life of his flesh and blood.

Frank Dolan ended his column in the Irish Post as follows: "You will, I am sure, join me in lifting your hat to William Flynn in Enfield, Co Meath. He is a rare species in Ireland – a truly decent man."

Last Sunday around 4.30pm, Billy finished up organising some work for the following day. He sat down on a couch in front of the TV as Eileen went to make tea. He was in good form. Sometime over the next few minutes, death stole into the house and took him. He was 64.

His family has suffered the kind of wrenching heartbreak that comes with losing a loved one before their time. For friends, a blazing light has gone out. No more will a dull afternoon be sparked into life by a phone call delivering the introduction, "Billy here", before launching into gossip, mischief and the inevitable cackle posed as a question: "Were you watching Browne last night?"

There will be no more startling indiscretions revealed with dramatic flourish around that snooker table. His infectious laughter has rung its last.

Democracy must also feel a loss. Awkward, dogged customers like Billy Flynn are indeed a rare species to be cherished. It's safe to say he left the world in a better state than he found it. Sleep tight, friend.

mclifford@tribune.ie