It took time for the news from Derry to sink in. The phone lines were poor and the reporters on the spot were finding it difficult to reconcile official claims with the accounts of eyewitnesses.
Early radio reports were sketchy. Shooting had started when some of those taking part in a banned civil rights march broke away and threw stones at a British army barricade. The soldiers had opened fire.
There were casualties - it was hard to tell how many. Someone who had friends in Altnagelvin telephoned the hospital: they couldn't be sure. But by teatime there were rumours of six dead and many more injured.
As the night wore on, disbelief grew with every call from our reporters in Derry, Dick Grogan, Martin Cowley and Nell McCafferty. Could we be sure that deaths or injuries weren't being counted twice?
Bodies had been seen, but how many? And why was there no word of casualties among the soldiers?
Then we heard a British army spokesman give a different version of events to the BBC. In his account, the soldiers had been forced to defend themselves against rioters, bombers and gunmen.
Three of those shot had been attackers caught in the act, throwing nail bombs at the barricades.
IRA snipers had fired from above. From Rossville street flats near the entrance to the Bogside or from the city walls? All of those killed or injured had taken part, first in an illegal march, then in a planned attack on the troops.
The officer spoke slowly, quietly in what he probably imagined to be an authoritative tone. This was, precisely, what had happened. The official account. The precision raised suspicions.
We didn't believe it and we weren't alone in our disbelief. The Manchester news editor of the Guardian, for whom I'd worked as a correspondent since 1970, telephoned to say that Simon Winchester, their man in the North, had been in Derry; he'd seen what had happened and disagreed with the official account.
The Guardian was preparing to carry Winchester's meticulously detailed report and the news editor anticipated trouble between Dublin and London. What did Jack Lynch have to say about it?
TO describe Mr Lynch's mood as angry would be a feeble understatement. He, too, had heard contradictory accounts of the day in Derry and had been in contact with the British prime minister.
Edward Heath's response was short, sharp and insulting: this was none of Mr Lynch's business. In diplomatic language, the contact had been unhelpful.
That night I walked past the offices of the British embassy in Merrion Square. A friend from Tipperary was the only other person on the street and, as we stood in the biting cold to stare at the shuttered windows, he swung his arms and laughed: "How long would you give it? 'Twill be gone by the end of the week."
He was right. There were nightly demonstrations in Merrion Square as more became known of what had happened in Derry and anger grew.
On the national day of mourning, the day of the funerals, tens of thousands led by the Irish Congress of Trade Unions marched through Dublin.
Gardai could only watch from a distance as the embassy burned while, across the square, members of the government and officials stood at the windows of Leinster House and Merrion Street - thankful, one said, that the crowd hadn't turned its attention elsewhere.
It wasn't only the deaths which fuelled the anger but the brazen pretence that excused the shooting and sought to saddle the dead with offences they hadn't committed.
This was the nadir of the Northern conflict: internment had been the object of the protest in Derry that Sunday; more people died in the fighting between 1970 and 1975 than at any other time; and in 1972 the governments had yet to find a way of working together.
There was also the shock of rediscovering how badly the forces of law and order could behave.
It was less than 2 1/2 years since the British army had been cheered into Derry and Belfast, and especially to the Bogside and the Falls Road, where the soldiers were seen as a welcome alternative to the B-Specials.
Many in the North had expected better of the British army and were disappointed. Many, too, held Britain's legal and political establishment in high esteem; and for them, what followed was as bad or worse.
The Widgery report didn't simply repeat many of the claims made by spokesmen on the spot, it added to them the weight and authority of the office of the Lord Chief Justice. Since 1972 the name Widgery has become a synonym for whitewash.
THOSE who feel that Tony Blair is wrong to hold a fresh inquiry should think again. Some say the Prime Minister is giving in to nationalist demands so that Sinn Fein may be persuaded to stay in the multi-party negotiations; others argue that he's responding to pressure applied by Bertie Ahern.
There is a much more powerful argument for holding the inquiry and it has little to do with political manoeuvring. Justice demands it, with greater force than any group or party. It's not a case of valuing Catholic lives more highly than the lives of Protestants; it's an acknowledgment of the value of life itself.
It's also recognition of the accountability of those who are obliged to protect the lives of citizens, as part of the administration of justice.
A fresh inquiry is not a reward for the persistence of the relatives and friends of those killed 26 years ago: justice is not a prize for persistence, it's a function of democracy. But the reputations of the men who died will be served by a thorough and impartial examination of the facts.
Anyone who feels tempted to take advantage of these deaths or this inquiry to promote violence or begrudgery on either side should be reminded of one of the principal reasons for the support won by the relatives in the course of their campaign.
The public response was greatly influenced by the knowledge that when those who died were accused of resorting to violence, it was their accusers who were in the wrong.
The Irish Congress of Trade Unions has once more raised its banners in protest against the murderous activities of paramilitaries. It has a long and respectable history of opposition to sectarianism, bigotry and violence.
One of its strengths has always been its refusal to take sides. Partisanship, of its nature, is the enemy of the unity the ICTU stands for - that of workers, irrespective of creed.