David was appointed a judge of the High Court in December 2017. He is currently assigned to the commercial division of that Court. He is also the judge appointed to hear challenges brought in respect of strategic infrastructure developments. In June 2018, he was appointed as the arbitration judge to hear all arbitration-related matters. He is chairman of Irish Rule of Law International and a governor of the National Maternity Hospital.

David was the chairman of the Council of the Bar of Ireland (2014-2016) and was a member of the  Legal Services Regulatory Authority. He was co-chair of the International Bar Association’s forum for barristers and advocates; vice-chairman of Sport Ireland’s Anti-Doping Disciplinary Panel and vice president of Arbitration Ireland; a former member of board of the Courts Service and of the Judicial Appointments Advisory Board; former vice-chairman of the Incorporated Council of Law Reporting for Ireland, of the Legal Aid Board, and of the Contracts Awards Committee of the Broadcasting Authority of Ireland. 

He is a Fellow (now a Judicial Fellow) of a number of different international trial lawyer bodies, including the International Society of Barristers and the International Academy of Trial Lawyers.

David was called to the Bar in 1990 and became a Senior Counsel in October 2006. He is a Bencher of the Honorable Society of King’s Inns in Dublin and of Middle Temple in London. While at the Bar, he practiced mainly in the areas of commercial law, administrative law, insurance law and product liability law. He was a CEDR Accredited Mediator and regularly acted in mediations and arbitrations (both domestic and international) in a wide range of cases as counsel or as mediator or arbitrator.