An intriguing legal problem. The issue with the Policy Exchange paper is that it fails to explain on orthodox principles of legislative interpretation how s 2 of the 2001 Act can be read in the way proposed. The provision says "shall", and the authors' contention is that this should be read as "shall not". Avoiding a breach of customary international law might be a reason to stretch the words, but it is difficult to see how it could entirely reverse their meaning. Perhaps the best answer is that the 2001 Act needs to be revisited in light of the ICC's interpretation of Article 98.
I think there is room to argue against the professors.
https://www.ejiltalk.org/the-bashir-appeal-at-the-icc/ – according to the decision in Prosecutor v Al Bashir, the ICC makes no difference between state and non-state parties of the Rome Statute for the purpose of executing arrest warrants. If the UK were to arrest Bibi, it would be acting in accordance with international law as laid out by the ICC, despite Israel not being a member of the ICC. While the decision is controversial, it reflects the current law.
An intriguing legal problem. The issue with the Policy Exchange paper is that it fails to explain on orthodox principles of legislative interpretation how s 2 of the 2001 Act can be read in the way proposed. The provision says "shall", and the authors' contention is that this should be read as "shall not". Avoiding a breach of customary international law might be a reason to stretch the words, but it is difficult to see how it could entirely reverse their meaning. Perhaps the best answer is that the 2001 Act needs to be revisited in light of the ICC's interpretation of Article 98.
I think there is room to argue against the professors.
https://www.ejiltalk.org/the-bashir-appeal-at-the-icc/ – according to the decision in Prosecutor v Al Bashir, the ICC makes no difference between state and non-state parties of the Rome Statute for the purpose of executing arrest warrants. If the UK were to arrest Bibi, it would be acting in accordance with international law as laid out by the ICC, despite Israel not being a member of the ICC. While the decision is controversial, it reflects the current law.
They respond in detail to the Bashir case in their earlier paper: https://policyexchange.org.uk/wp-content/uploads/The-International-Criminal-Court-Act-2001-and-State-or-Diplomatic-Immunity_.pdf