Robert McCartney was murdered by an IRA gang which had, ironically, just returned from mourning the dead of another infamous injustice – the Bloody Sunday massacre of 1972.
The men who murdered McCartney, seriously injured Brendan Devine, the friend he tried to help, and then covered up their crime and threatened witnesses, had been to Derry for the 33rd anniversary of the killing of 14 unarmed civilians by the Parachute Regiment.
After attending the commemoration on January 30, 2005, the IRA members from Belfast's Short Strand, Markets and Lower Ormeau Road areas returned to the city and opted to end the evening with a few drinks in Magennis's bar.
It was a decision that was to prove fatal for McCartney, as was his choice of drinking companion. There had been a history of animosity between Devine and some IRA men. So his presence in the pub full of IRA members and supporters created a tense atmosphere.
The fight that led to McCartney's death was sparked by allegations of rude gestures being directed at the wife of an IRA member. The row was initially calmed but one man, a former IRA Belfast brigade commander, was not satisfied.
According to the McCartney sisters, the Police Service of Northern Ireland and local reports, this man told henchmen to assault Devine who was slashed in the neck and smashed over the head with a bottle.
McCartney helped Devine, who was bleeding profusely, out of the bar to try and call an ambulance. Up to eight people followed the pair outside and witnesses later reported that the men were punched, beaten and stabbed.
There were, however, no witnesses in the bar. All of the 72 drinkers told detectives they were in the toilet when the assault happened. Wags in Belfast remarked that Magennis's should be in the Guinness Book of Records because of the number of people packed into toilets.
Two cover-ups ensued which were to rebound badly on the IRA and Sinn Fein and have profound consequences for the peace process.
The first was immediate. Customers were told not to report anything they had seen as this was "IRA business". The gang involved then forensically cleaned the pub, disposed of the knife and other weapons and orchestrated a riot the following day to prevent police from searching the nearby Markets area.
The second cover-up was political . Sinn Fein initially tried to paint the murder as just another example of knife crime and denied any of their members were involved. When it transpired that the suspects included James McCormick, the party's treasurer in south Belfast, election workers and stalwarts of the Provisional IRA, Gerry Adams and co switched tactics.
They invited the McCartney sisters to their annual conference just a few weeks after the murder but failed to encourage anyone to give evidence to the police. Moreover, the IRA was reported to have offered to shoot its members involved in the killing although Catherine McCartney denied this.
Sinn Fein's obfuscation cost Adams his annual invite to the White House for Saint Patrick's Day. George Bush met with the McCartney sisters and Bridgeen Hagans, the mother of McCartney's two young boys, in the Oval Office instead.
The impact of the killing was not just a snub to Adams. The Bush administration saw the issue as a key test of Sinn Fein's bona fides for re-entering a powersharing government with Unionists.
Bush's special envoy to Northern Ireland , Mitchell Reiss, put enormous pressure on the republican movement and the British and Irish governments saying it was time for Sinn Fein to make an historic shift in its policing policy.
Reiss pointed to Sinn Fein's ambiguity over the McCartney issue and the ongoing intimidation of witnesses as a compelling reason for the republican movement to change its stance.
What began as a bar brawl became an international struggle for justice and caused such an embarrassment that it accelerated the republican movement's acceptance of policing within Northern Ireland.