Fleming was killed along with fellow volunteer Danny Doherty after they were ambushed in the grounds of Gransha Hospital by Special Air Service (SAS) and 14 soldiers of the British Army on 6 December 1984.
In 1984 Fleming spent a week in Hydebank Detention Centre in Belfast after he refused to pay a fine he was given after being found guilty of damaging a Royal Ulster Constabulary vehicle.
On 6 December 1984, Fleming and Doherty were riding around on a motorbike in the grounds of Gransha Hospital, approximately four miles from Derry city centre.
An SAS unit from the Londonderry Detachment of 14 Intelligence Company, without the knowledge of the Royal Ulster Constabulary or the hospital authorities, located troops at the site keeping watch for two weeks prior to 6 December.
"[7] Gregory Campbell, Democratic Unionist Party spokesman, said "I am delighted that the two IRA men were intercepted and executed by the undercover army unit.
"[3] John Hume then Social Democratic and Labour Party leader told the House of Commons, "This raises very fundamental questions as to whether the authorities have abandoned the rule of law, and whether we are now in a war situation.
In excess of 3,000 mourners followed the funeral procession to the City Cemetery in Derry where Sinn Féin's Martin McGuinness gave the graveside oration, and stated: '"We are an occupied country and those brave enough to fight repression deserve nothing but respect and unfailing support from us all.
Though the application for the judicial review failed, the jury at Doherty's inquest did criticise the five-man army unit for not attempting to arrest him or inform the RUC of the operation earlier, through which they suggested his life might have been saved.