On 31 December 2020, when the transition period provided for in the Withdrawal Agreement between the EU and the UK comes to an end, EU law will cease to apply in the UK. However, large parts of the law currently applicable in the UK which is derived from EU law or is directly effective EU law will continue to apply as “retained EU law”.

In interpreting this retained EU law:

• UK courts will apply decisions of the Court of Justice of the European Union (“CJEU”) that pre-date the end of the transition period, save to the extent that particular courts are given power to depart from those decisions. The European Union (Withdrawal) Act 2018, as originally enacted, provided that the Supreme Court (as well as the ultimate court of appeal on Scottish criminal law) would have such power. Following a consultation by the Ministry of Justice, such power will now also be extended to other appellate courts, including the Court of Appeal.
• CJEU decisions post-dating the end of the transition period are not binding on UK courts but the courts may have regard to them so far as relevant.

For more information, see this post on our Beyond Brexit blog.