Sir Wyn Williams accepts appointments as an arbitrator and mediator for both domestic and international disputes.
Sir Wyn was appointed a Recorder of the Crown Court in 1992 and a deputy High Court Judge in 1999. He took up a full time judicial appointment on 1 April 2004 when he was made a senior circuit judge and the specialist Chancery Judge for the Wales and Chester Circuit. In January 2007 Sir Wyn was appointed to the High Court and immediately upon appointment he was authorised to sit in the Administrative Court. Between 1 January 2012 and December 2015 he was a presiding judge for Wales becoming the Senior Presiding Judge in January 2014. Although Sir Wyn has retired as a full time judge he is authorised to sit as a deputy High Court Judge. In December 2018, Sir Wyn was sworn in as a Court of Appeal Judge for Guernsey.
Between September 2012 and July 2016 Sir Wyn was the Deputy Chairman of the Boundary Commission for Wales; between 2103 and his retirement in 2017 he was the Chairman of the Wales Committee of the Judicial College. In 2013 Sir Wyn was elected to a fellowship of The Learned Society of Wales in recognition of his services to the law in Wales.
Prior to taking up a full time judicial career, Sir Wyn had a broad and highly successful practice at the Bar. He was called to the Bar in 1974 and practised from Chambers in Cardiff until 1998. He took silk in 1992. In October 1998 he joined 39 Essex Chambers in London. In his later years as a silk he practised principally in personal injury, clinical negligence, sports and public law but developed a particular interest in sporting disputes.
Sir Wyn has extensive experience in sports law as a barrister, judge and mediator. He is a member of the Sports Resolutions’ Arbitration Panel and examples of work in this area include:
As a High Court Judge:
Sir Wyn has extensive experience over a wide range of public law. Examples of work in this area include:
As a QC:
Sir Wyn acted for private clients and planning authorities in a large number of planning cases. He was instructed at planning enquiries and appeals for and against promoters of road schemes, housing developments and other major projects. He also acted for developers and planning authorities in legal challenges brought in the High Court relating to planning decisions made by planning authorities and inspectors on appeal.
Immediately prior to taking up the first of his full time judicial appointments Sir Wyn acted as leading counsel for the Secretary of State for the Home Department in appeals brought before the Special Immigration Appeals Commission by persons who had been detained on suspicion of engaging in international terrorism. The legislation authorising detention was highly controversial and brought into force as one of a number of counter-terrorism measures in the aftermath of 9/11.
As a High Court Judge:
Sir Wyn sat regularly in the Administrative Court throughout his career as a High Court Judge and he was authorised to hear all the various types of cases litigated in that court. Upon the creation of the Planning Court Sir Wyn became of judge of that Court. Sir Wyn has presided over public law cases involving human rights, terrorism, extradition, immigration, planning, education, community care and mental health. Sir Wyn has also done a considerable amount of “regulatory work” when sitting in the Administrative Court. He has presided over challenges/statutory appeals from bodies such as the Bar Standards Board, the Solicitors Regulation Authority, the General Medical Council, the Nursing and Midwifery Council, the Health Care Professional Council and the governing bodies of dentists, accountants and teachers.
As a junior barrister and silk Sir Wyn was very heavily engaged in a variety of common law cases. Examples of work in this area include:
As a QC:
Sir Wyn had an extensive practise in personal injury and clinical negligence claims. In clinical negligence claims he was usually instructed on behalf of the Claimant but in personal injury claims arising from industrial accidents or road traffic accidents he was instructed by both Claimants and Defendants. In the main, the cases in which Sir Wyn was involved related to catastrophic injuries but he also undertook work in relation to industrial disease, especially disease caused by exposure to asbestos.
As a High Court Judge:
Sir Wyn has presided over trials in the Queen’s Bench Division relating to a wide variety of legal topics. Examples of such cases are Chandler v Cape Plc  EWHC 951 (QB) (liability of non-employer for exposure to asbestos), Kynixa Ltd v Hynes and others  EWHC 1495 (QB) (claims arising from alleged breaches of restrictive covenants in employment contracts), Romantiek BVBA v Simms  EWHC 3099 (QB) a claim alleging that a public official had committed the tort of misfeasance in public office when discharging a licensing function, OOO and others v The Commissioner of Police for the Metropolis  EWHC 1246 (QB) (claims by young foreign females that they had been trafficked into the UK by foreign nationals for the purpose of slavery and that officers of the Metropolitan Police Force breached their human rights in failing to investigate their complaints adequately or at all) and Mouncher and others v The Chief Constable of South Wales Police  EWHC 1367 (QB) (claims by retired and serving police officers for false imprisonment, misfeasance in public office and malicious prosecution against South Wales Police arising from an investigation by officers of that force into alleged criminal conduct on the part of the claimants during the course of an investigation into a notorious murder in South Wales.
During his time as the specialist Chancery Circuit Judge for the Wales and Chester Circuit Sir Wyn tried most of the important chancery cases arising throughout Wales and Cheshire. He also sat as a deputy High Court Judge in the Chancery Division in Wales, Chester and London. Amongst the cases over which Sir Wyn presided were shareholder disputes and other company law disputes, real property disputes, disputes arising from wills and intestacy, partnership disputes and a wide range of claims relating to or arising from insolvency. Following his elevation to the High Court Bench Sir Wyn sat occasionally in the Chancery Division of the High Court both in London and in Wales. He also tried public law cases which had a strong Chancery element. Examples are Cameron and others v Commissioner for HM Revenue and Customs  EWHC 1174 (Admin) (a dispute between the Inland Revenue and seafarers about taxation provisions) and Evans v Wimbledon and Putney Commoners  EWHC 3411 (Admin) (a dispute about the extent of the power to grant property rights such as easements over Wimbledon Common.