Compulsory in Name Only: Canada’s Effective Withdrawal from ICJ Optional Clause Jurisdiction

On 28 August 2023, Canada amended and substantially narrowed its unilateral declaration accepting the compulsory jurisdiction of the International Court of Justice (ICJ). The combined effects of its various reservations — notably, Canada’s new requirement that states must have provided at least six-month advance written notice before instituting ICJ proceedings against it, coupled with its ongoing rights to amend or terminate its declaration with immediate effect — have now rendered Canadian acceptance of Optional Clause jurisdiction compulsory in name only. Canada now appears to control whether any future ICJ cases can ever be brought against it in this way.