Timothy is instructed in both direct and indirect tax cases in relation to the affairs of companies, multi-national enterprises and high net wealth individuals. A considerable proportion of his work involves international matters and he is frequently asked to address EU law and international law issues. Most of the time his cases concern situations in which disputes have arisen or are anticipated. He appears as an advocate in the Commercial Court, the Administrative Court and the Court of Justice of the EU as well as in courts at all levels in tax appeals. He works with lawyers, accountants and tax and customs advisers based in the UK and elsewhere in Europe, as well as in Asia and America.

Timothy is well known for his work in EU customs law, trade defence law, including EU anti-dumping law, and EU state aid law. The impact of state aid law on tax rulings and settlements is an area of particular interest. He has recently addressed the internal market and consumer protection committee of the European Parliament in relation to customs sanctions.

His practice continues to include work for private clients and he is one of the rapporteurs for the European Commission’s Expert group on removing tax problems facing individuals who are active across borders within the EU.

Timothy became a QC in 2003 and was called to the Irish Bar in 1998.