[citation needed] Kelly joined the IRA in the early 1950s when he was 18 and took part in the Border Campaign of 1956–62, but was arrested in December 1956 and was imprisoned until 1963.
A leader of the newly formed Provisional IRA in 1969, he was involved in the formation of "citizens' defence groups" to protect nationalist areas of Belfast from loyalist rioters who were largely unhampered by the police.
[4] Kelly was deselected before the 2003 election, and criticised the decision by the Sinn Féin leadership to support policing reforms.
In January 2006 he co-wrote a letter with Brendan Hughes which cast doubt on the claims that dissident republicans had threatened Sinn Féin leaders and claimed that the real threats were being made by the Sinn Féin leadership against those who sought a debate on policing.
He left Sinn Féin which he considered too controlled from the centre, opposing the leadership: "deceit and the philosophy of creative ambiguity", and retired from politics.
[5][6] Many tributes have been paid to him including a minute's silence before the Derry Senior Football Championship quarter final between An Lúb and Dungiven on 8 September 2007, at the home of his local club, Watty Graham Park, Glen.