If passed by the UK parliament, the bill will transpose into UK law the revised UK withdrawal deal agreed earlier this month by the UK and EU. The deal, which must now be ratified by the UK and the EU in advance of exit day, sets out the proposed terms of the UK's exit from the EU and Euratom. While similar to the deal previously agreed by Theresa May's government and the EU, the revised agreement removes the controversial 'Irish backstop' and sets out compromises for both the UK and EU.
The bill provides for the repeal of the European Communities Act as of the date of the UK's withdrawal from the EU. A transitional 'implementation period', during which EU law would continue to apply, would then run until the entry into force of a new economic partnership between the UK and the EU. The implementation period is due to end on 31 December 2020, but may be extended once for up to one or two years. Only the UK government, not the UK parliament, may request an extension to the implementation period.
Litigation expert Craig Connal QC of Pinsent Masons, the law firm behind Out-Law, said that while EU law would continue to apply in the UK during the implementation period, this would only be "because the Act says so, not because of EU membership". On a practical level, this would require the UK to keep up to date with EU legislative changes for the duration of the implementation period, he said.
"Since the UK has become accustomed to operating under EU law, it should be feasible for it to continue to do so until the end of the implementation period," he said.
"UK courts will be obliged to follow EU legal rulings during the implementation period. After this point, EU law will no longer be binding but the courts will have to give it 'due regard' in appropriate cases. In the past, there have been cases where a UK court applying EU law has, in effect, been overturned by the Court of Justice of the EU, but this would no longer be the case," he said.
A new protocol dealing with the UK's land border with the EU, between Northern Ireland and the Ireland, is intended to apply from the end of the implementation period. To avoid a 'hard' border on the island of Ireland, new customs and regulatory arrangements will operate between Northern Ireland and Great Britain. The bill provides the legislative underpinning for these arrangements, and gives the government extensive powers to put the new arrangements in place through secondary legislation.
The bill does not offer the same security in relation to protecting workers' rights that was written into the legislation of May's withdrawal agreement, instead offering only a "watered down" protection, according to employment law expert Euan Smith. Once the implementation period has passed, the government would be required to notify parliament before introducing any "regression" of workers' rights originally derived from EU law.