Carriers transporting third-country nationals by air, sea, or land to the Schengen area are required to take all necessary measures to ensure that these individuals hold the travel documents needed for entry into the Schengen States. The European Commission has launched three ad hoc queries, each focusing on a specific aspect of carriers’ liability: the framework of sanctions and penalties; responsibility for costs; and cooperation with carriers and control/supervision.

In its judgment in Case C-679/23 P (WS and Others v Frontex), the Court of Justice of the European Union found that Frontex has specific obligations under EU law in joint return operations, including verifying the existence of enforceable return decisions for all persons involved. The ruling also emphasised that infringements of fundamental rights during such operations may give rise to the agency’s liability.