In July 2023, the Nova Scotia government filed notice with the court concerning the constitutional responsibility for infrastructure that protects the interprovincial transportation, trade and communication links across the Chignecto Isthmus, a 35-kilometre strip of cross-border land.

Nova Scotia, New Brunswick and Prince Edward Island want the court to settle the constitutional question of whether the transportation, trade and communication links across the Chignecto Isthmus are within the exclusive legislative authority of Parliament.