Brexit: Three Matrix members successful in Article 50 claim in High Court


Helen Mountfield QC, Jessica Simor QC and Rhodri Thompson QC have been successful in representing the claimant parties in their challenge to the procedure for triggering the UK’s withdrawal from the EU under Article 50 of the Treaty on European Union. The High Court today rejected the argument that the Government may make the Article 50 notification without an Act of Parliament, and found the Government does not have authority to do so under the Royal Prerogative.

Handing down the judgment, the Lord Chief Justice (Lord Thomas of Cwmgiedd), Master of the Rolls (Sir Terence Etherton) and Lord Justice Sales, ruled that since the enactment of the European Communities Act 1972, no prerogative power existed to remove rights conferred through that legislation. The Court considered the sovereignty of Parliament to be critical, stating that the Government is not entitled to change domestic law enacted by Parliament. These fundamental constitutional principles led the High Court to reject the Government’s argument.

The full judgment and a summary is available on the judiciary.gov website.