Catherine specialises in a number of Chambers’ practice areas, including EU Law, Public Law, Human Rights and Commercial Law and appears before both the national courts and tribunals and the Court of Justice of the European Union.

Catherine combines her practice with a number of appointments and with her academic position as Associate Professor and Fellow of Trinity College, Dublin and her position as Chair of the Irish Society for European Law and Member of the Incorporated Council of Law Reporting for Ireland.



EU & Competition

Catherine has appeared in a number of cases involving EU law before the Court of Justice of the European Union, the courts of England and Wales and the High Court, Court of Appeal and Supreme Court of Ireland.  

Recent cases before the Court of Justice include:  

  • Case C-613/14 James Elliott Construction Limited v Irish Asphalt Limited (Advocate General Opinion, 28 January 2016). 
  • C-398/11 Hogan v Minister for Social and Family Affairs (25 April 2013). 
  • Case C-370/12 Pringle v Ireland (23 November 2012) (challenge to the European Stability Mechanism before the Grand Chamber of Justice of the European Union).

Catherine acts in cases involving public procurement law, competition law, state aid law, data protection, access to environmental information and planning in accordance with the requirements of EU law.   

Catherine has also advised and acted for a variety of public authorities and private clients on EU law matters, including the Office of Communications Regulation in Ireland, the Office of Corporate Enforcement, the Medical Council of Ireland, the Commission for Communications Regulation, the Information Commissioner, the Health Information and Quality Authority, the Data Protection Commissioner, the Office of the Revenue Commissioners, the Irish Aviation Authority, IDA Ireland, An Post, Ireland West Airport Knock, Irish Waterways, An Taisce, various local authorities and the National Bus and Railworkers’ Union.

Catherine has represented clients in a number of matters in the Competition List in Dublin, including, in particular, proceedings involving a claim of refusal to supply (Heatons v ASICS UK Limited (Cooke J) 1 November 2013). 


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Catherine has been listed in the International Who’s Who of Public Procurement lawyers in 2012-2015. She also advises both potential claimants and contracting authorities in this field and has advised a number of contracting authorities on the conduct of their procurement processes. Recent cases have included:  

  • Student Transport Limited v Minister for Education and Skills (Court of Appeal Judgment Pending)
  • RPS Consulting Engineers Limited v Kildare County Council (15 February 2016)  
  • Powerteam Electrical Services Limited Trading as Omexom v Electricity Supply Board (12 February 2016)
  • BAM PPP PGGM Infrastructure Cooperatie UA v National Treasury Management Agency & anor [2015] IEHC 756
  • BAM PPP PGGM Infrastructure Cooperatie UA v National Treasury Management Agency & anor [2015] IECA 246 
  • Word Perfect Translation Services Limited v Commissioner of An Garda Síochána [2015] IEHC 668 
  • BAM PPP PGGM Infrastructure Cooperatie UA v National Treasury Management Agency & anor [2015] IEHC 370
  • Student Transport Limited v Minister for Education and Skills [2015] IECA 303 
  • OCS One Complete Solution Ltd v Dublin Airport Authority PLC [2014] IESC 51 
  • OCS One Complete Solution Ltd v Dublin Airport Authority PLC [2014] IEHC 306 
  • Gaswise Limited v Dublin City Council [2014] IEHC 56 
  • Baxter Healthcare Limited v Health and Safety Executive [2013] IEHC 413 
  • O’Kelly Brothers Civil Engineering Company Limited v Cork City Council [2013] IEHC 159
  • Student Transport Limited v Minister for Education and Skills [2012] IEHC 425


State Aid

In the state aid context, as well as advising frequently in this area, Catherine appeared in the case of Dellway v National Asset Management Agency [2010] IEHC 364; [2011] 4 IR 1, which involved a challenge to the acquisition by Ireland’s National Asset Management Agency of certain loans; the case raised a range of public law and EU law questions, including a number of state aid issues.  



Catherine has acted in and worked on telecommunications cases (e.g. R (on the application of ICO Satellite Ltd) v Ofcom [2011] EWCA Civ 1121) and CAT appeals. She is also currently representing a consortium in its challenge to alleged corruption and breach of national and Union law in the award of a mobile phone licence in Ireland, Comcast International Holdings v The Minister of Public Enterprise [2014] IEHC 18. She has also acted for the Commission for Communications Regulation in a number of matters.


Data Protection, Freedom of Information & Privacy

Catherine frequently provides advice on data protection questions, to both public and private sector clients.



Catherine is currently acting in a series of actions involving assertions of mis-selling of products, misrepresentation, breach of contract, and professional negligence. She has represented clients in a large number of cases in the Commercial Court in Ireland, and many of the procurement cases listed above were conducted in the Commercial Court. 

Catherine acted for the claimant in a 104-day trial in the Commercial Court in a negligence and nuisance claim against the Electricity Supply Board for flooding of Cork City in 2009: University College Cork v Electricity Supply Board [2014] IEHC 135 and [2015] IEHC 598.  She is also acting in a number of shareholder dispute cases and currently represents PriceWaterhouseCoopers in an auditor negligence claim: Quinn Insurance Limited (Under Administration) v PriceWaterhouseCoopers [2015] IEHC 303.

Catherine has acted in intellectual property claims, including urgent injunction applications in the context of passing off (e.g. Dublin Bus v Citibus).


Public & Regulatory

Since commencing practice, Catherine has experienced a broad range of public law work, in both the regulatory and telecommunications field and in judicial review cases involving human rights.  

She has represented both claimants and defendants in judicial review and human rights proceedings before the Courts of England and Wales, including in the Court of Appeal, before the Courts of Ireland, the European Court of Human Rights (including Donohue v Ireland, 12 December 2013) and in cases before the European Social Committee. 

She has acted for the General Medical Council, the Office of Communications Regulation in Ireland, the Information Commissioner (Westwood Club v Information Commissioner [2014] IEHC 375), the Health Information and Quality Authority, the Office of Revenue Commissioners, the Irish Aviation Authority (including in McMahon v Irish Aviation Authority [2014] IEHC 431), IDA Ireland and various local authorities.   

She is currently acting for the Public Accounts Committee of the Irish Parliament in judicial review proceedings raising issues of legality, fair procedure and misfeasance in public office: Kerins v McGuinness [2015] IEHC 293 and [2015] IECA 267.  

She also represented the Irish Referendum Commission in its resistance to a challenge to the 2015 Marriage Equality Referendum in Ireland (Walshe v Ireland, The Attorney General, The Referendum Returning Officer and The Referendum Commission [2015] IESCDET 37). 

She has represented Ireland in a number of cases (including: Donohue v Ireland; Pringle v Ireland (High Court and Supreme Court); Byas v County Registrar for the County of Dublin Ireland and Attorney General; O’Driscoll and McCarthy v Limerick City Council, Ireland and Attorney General [2012] IEHC 594; Fitzsimons v County Registrar for the County of Meath, Ireland and the Attorney General; and Heffernan v County Registrar for the County of Dublin, Ireland and the Attorney General).  

On the claimant side, Catherine appeared in the High Court and Supreme Court in a case involving a constitutional challenge to a referendum held in Ireland on the basis that the Government had breached constitutional requirements not to expend public moneys advocating a particular outcome in the referendum and relying on the Venice Commission Code for Good Practice on Referendums: Jordan v Minister for Children and Youth Affairs [2013] IEHC 458, [2013] IEHC 625, [2014] IEHC 327, and [2014] IESC 33.  She also appeared in Barlow v Minister for Agriculture, Food and the Marine [2014] IEHC 471 (Supreme Court ruling pending), involving a constitutional challenge to management of mussel seed resource.  

She has acted for the Northern Ireland Human Rights Commission, including advising the Commission on its recommendations for a Bill of Rights for Northern Ireland in 2008. The work involved advising on all areas of European and international human rights law, administrative law and constitutional law relating to both the content and the implementation of the Commission’s recommendations, and drafting those sections of the Commission’s final advice. The work also entailed advising on precise formulations and wordings of the particular rights.  

More generally, Catherine advises and represents both public and private sector clients, including NGOs – such as the National Secular Society, the Transgender Equality Network Ireland, Free Legal Advice Centre, the Committee on the Administration of Justice, An Taisce, and the Northern Ireland Council of Ethnic Minorities, the Irish Human Rights and Equality Commission – on a variety of public law and human rights issues, including the Charter of Fundamental Rights of the European Union, the ECHR, the Irish Constitution, the public sector equality duty, and the Hong Kong Bill of Rights.  

Catherine is also one of the editors of De Smith’s Judicial Review (2007, 2009, 2013, 2014 and 2015).


Public International Law

A large part of the advisory work Catherine does in Northern Ireland involves international law, and she has advised on the interpretation of various conventions and treaties, and most particularly, international human rights instruments. In 2007-2008, Catherine was appointed to advise the Northern Ireland Bill of Rights Forum, (to which she was a Legal Advisor from September 2007 to March 2008) on matters of international law. She also regularly advises the Northern Ireland Human Rights Commission and NGOs in Northern Ireland on difficult questions of interpretation of the Good Friday/Belfast Agreement and other Anglo-Irish Agreements and treaties.  Catherine also acted in the case of Barlow v Minister for Agriculture, Food and the Marine, which involved questions of the Law of the Sea.



Catherine has experienced a number of trials in the Employment Tribunal, as well as before Equality Officers and the Labour Court in Ireland. She has appeared in cases involving constructive dismissal, unfair dismissal, wrongful dismissal, discrimination on grounds of sex and race, TUPE, and whistleblowing. She has also advised on domestic and European employment law obligations. She has also appeared in the High Court of Ireland in cases involving urgent injunctions in the employment context for both claimants and defendants.



LLB (Trinity College, Dublin); BCL (Oxon); LLM (Harvard); DPhil (Oxon)


  • Jan 2007 - date, Associate Professor and Fellow, Trinity College Dublin 
    Courses: Advanced European Union Law, Comparative Public Law, Human Rights Law, Public Procurement Law. 
  • Apr - Dec 2008  Northern Ireland Human Rights Commission
  • Principal Legal Adviser to the Northern Ireland Human Rights Commission on the drafting of a new Bill of Rights for Northern Ireland.  The work involved ensuring that the rights proposed by the Commission in its advice were “supplementary” to the ECHR and in accordance with relevant international human rights standards. Advice also given on the implementation and enforceability of the proposed rights. Drafted those sections of the Commission’s Advice which explained the supplementary nature of the recommended rights and their compliance with international human rights standards. The Advice was published on 10 December 2009.
  • Sep 2007 - Mar 2008  Northern Ireland Bill of Rights Forum
    Adviser to the Bill of Rights Forum on the drafting of, and legal issues arising from, a new Bill of Rights for Northern Ireland.  Advice given on defining a “public authority”, devolution, drafting a preamble, human rights, implementation, interpretation, justiciability of socio-economic rights, mainstreaming human rights, remedies, and standing.  
  • Oct 2005 – 2007 CUF Lecturer in Law (University) and Fellow of Wadham College, Oxford  
    Courses: Administrative Law, Constitutional Law, European Community Law (constitutional and substantive) (undergraduate and postgraduate students).
    Lecture Series: Administrative Law in Context; Constitutionalism in the EU; The Multi-Layered Constitution.
  • 2003 - 2004 Corpus Christi College, Oxford
    College Lecturer.  Taught Administrative Law to undergraduate students from Corpus Christi College and St. John’s College.  
  • Sep 1999 - Sep 2001  Davis Polk & Wardwell, Attorneys-at-Law, New York
    Litigation Attorney (Associate)
    Areas of Practice: Administrative Law, Antitrust, Asylum Law, Commercial Arbitration, Constitutional Law, Criminal Law, Fraud, Regulation, Securities, White Collar Crime. 

VAT registration number: 941200568

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