Former Fianna Fáil Senator James Carroll was Education Officer and later President of the Students' Union in UCD; and Mayor of Derry Martin Reilly was a sabbatical officer in Queens. Christopher Stalford MLA, Lord High Sheriff of Belfast and youngest ever member of Belfast City Council was a prominent activist in Queens Students' Union and a student representative on the Senate of QUB, and Simon Hamilton, Stormont Finance Minister also represented students on the Senate of Queens. Jemma Dolan, Sinn Féin MLA for Fermanagh and South Tyrone was Vice President for Campaigns and Communications for the University of Ulster Students Union. Political activist and victim of the miscarriage of justice after the Sallins Train Robbery, Osgur Breatnach, was a member of the Students' Representative Council of UCDSU. Irish Ambassador to the United Kingdom Dan Mulhall was Deputy President of the Students Union in University College Cork. Aviation Regulator Cathal Guiomard and Central Bank of Ireland Commissioner Neil Whorisky were both Presidents of UCGSU. Sailing personality Enda O'Coineen was sports officer on UCG's Union Executive, and debt relief activist and campaigner David Hall was Vice-President of the Students' Union in Maynooth in the 1990s. David O'Sullivan, later Secretary General of the European Commission, was noted during his student days as a moderate voice in the Students' Union in Trinity College.