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Declan O'Callaghan

Year of call: 1995

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Practice Summary

Declan was awarded a Master's degree in international law from the University of Nottingham and has lectured on public international law for several years as a Visiting Scholar at the University of Exeter.

He has regularly lectured on public international law matters at various universities in England, India and Malaysia and presented lectures and seminars on human rights issues in Spain, Armenia, Norway, Turkey, Dubai, Uganda and Malawi.

Declan is a member of the Hong Kong Institute of Arbitrators.

He is active in death penalty work, both as a practitioner and by presenting seminars to members of the judiciary and the legal profession.

Declan is presently acting as Court-appointed Amicus Curiae in some 600+ “Kigula beneficiaries” sentencing appeals before the Ugandan High Court (from November 2013). The hearings concern the re-sentencing of persons convicted of capital crime offences following the declaration that the imposition of the mandatory death penalty was unconstitutional in Attorney General v Kigula & 417 Others (Constitutional Appeal No. 03 of 2006) [2009] UGSC 6. The re-sentencing process is concerned with the imposition or otherwise of a discretionary death sentence. Click here for full details of Declan's death penalty work.

He has conducted seminars on international law and the death penalty to the judiciary and lawyers in Uganda and Malawi (2011, 2013 and 2014). He has also presented workshops addressing mitigation to death row prisoners at Luzira Prison, Kampala, Uganda in 2011 and 2013.

Declan was a member of the International Bar Association team lecturing Iraqi judges and prosecutors on international humanitarian law and capital crimes (2005-2006).

He has presented workshops in India concerning the United Nations and minority rights.

He was a Legal Assistant in The Prosecutor v Justin Mugenzi & Others (“The Government II Case”) at the International Criminal Tribunal for Rwanda (ICTR) from November to December 2008. 

He has acted as a spokesperson for the International Bar Association at a number of media events. 

Declan has presented a number of lectures and seminars on international law, both in the United Kingdom and overseas, including:

  • “Judicial Consideration of the Death Penalty outside of the United States of America” at the University of Oxford, International Human Rights Law summer school (July 2015)

  • “Lawyers and Ethics” at the University of Makarere, Kampala, Uganda (October 2013)

  • “Mitigation and Sentencing in Death Penalty Matters” to Supreme Court and High Court Justices, Blantyre, Malawi (November 2011)

  • “The Ramifications of the Media Case: The Prosecutor v Nahimana”, School of Oriental and African Studies, University of London. Fellow speakers included HH Judge Howard Morrison, Judge of the ICTY (now judge of the ICC) (October 2009).

Declan is recommended as a leading barrister for immigration by Chambers & Partners, and for immigration and administrative & public law by the Legal 500.