Dr Thomas Leahy is a senior Lecturer in British and Irish Politics/Contemporary History at Cardiff University in Wales. He is author of The Intelligence War Against the IRA (Cambridge 2020), which won the Political Studies Association Ireland’s Brian Farrell book prize in 2021 and was shortlisted for the Royal Historical Society's Whitfield Prize. He is an expert on Irish Republicanism and conflict legacy on the island of Ireland. He has regularly contributed to media items (television and radio) on his NI/ROI politics and conflict expertise, including with BBC News, RTE, The Irish Times and more. He also has presented his work to public audiences through discussion events at Cardiff University and via the Good Listener Podcast, Faculti alongside Trasna na Tire online lectures. 

He is currently involved in multiple research projects including on the decommissioning of weapons in Northern Ireland, how the Irish Government deals with NI conflict legacy in the Republic of Ireland, Sinn Féin, comparisons between Sinn Féin and Euskal Herria Bildu Basque left-wing nationalists, how MPs in and abouts NI influence Oireachtas and Westminster politics since 1998.

Recent publications

Iker Erdocia and Thomas Leahy, 'To Abstain or to take your seats? A comparison of Sinn Féin and lleft-wing Basque nationalists Euskal Herria Bildu policies towards abstentionism in Westminster and Madrid, 1998-2024' (forthcoming 2024). 

 'Tactical Use of Armed Struggle: The IRA's Purpose in Irish Republican Leadership Strategy, 1969 to 1998' (forthcoming 2024). 

'Re-evaluating the decommissioning of Irish Republican Army (IRA) weapons in Northern Ireland Part 1: August 1994 to October 2001' (forthcoming 2024). 

Niall Ó Dochartaigh and Thomas Leahy, ‘Withdrawal on the table? British policy on constitutional change in Northern Ireland’ (forthcoming 2024).

The Intelligence War Against the IRA (Cambridge: Cambridge University Press, 2020, paperback and hardback).

‘‘Rigorous impartiality’? The UK Government, Amnesties and Northern Ireland Conflict Legacy 1998-2022’, in Laura McAtackney and Máirtín Ó Catháin, The Routledge Handbook of the Troubles (London: Routledge, 2024).

Eleanor Leah Williams and Thomas Leahy, ‘The ‘Unforgivable’?: Irish Republican Army (IRA) informers and dealing with Northern Ireland conflict legacy, 1969-2021’, in Intelligence and National Security (2022)

'The politics of Troubles memories in Northern Ireland and the Republic of Ireland, 1998 to 2018' in Innovation: The European Journal of Social Science Research (2019).

Thomas Leahy and Niall Ó Dochartaigh, ‘Citizenship on the ethnic frontier: nationality, migration and rights in Northern Ireland since 1920’, in Steven G. Ellis (ed.), Enfranchising Ireland?: Identity, Citizenship and State (Dublin: Royal Irish Academy, 2018).