The EU model deals with the relationship between passengers and the airlines. It is without prejudice to the airline's right, then, to recover costs from a third party for damages. What we need to bear in mind is that both under the EU law and under the Montreal Convention, which is an international treaty, the airline is the passenger's final address for issues.
For example, if the passenger's baggage, after it was checked in, is damaged by security, then the passenger claims the baggage damage through the airline. The airline can then talk to CATSA or any other security agency to recover those damages, but insofar as the passenger is concerned, it is a matter between the passenger and the airline.
We also understand that these are complex systems. The European Union's regime recognizes the notion of an extraordinary circumstance like a snowstorm or volcanic eruption, which relieves the airline from the obligation to pay compensation. However, most situations relating to ground crew, fuelling aircraft and ensuring they have sufficient crewing and that they planned their flights properly are within the airline's control.
Airlines, even in Canada, had all the information they needed to estimate the problems that would be happening in the summer. They had all the information they needed in order to know what would happen and to know that perhaps CATSA or the airport facilities were imperfect, but they were still not able to handle the volume of traffic reflected by the sales of tickets by airlines.
What happened this past summer was a situation in which airlines were overselling the airport facility's capacity and they knew it perfectly well. That would have been, in the European situation, within the airline's control. It would be a whole different situation if, for example, God forbid you had an air crash, you had to close one of the runways suddenly and it was not known in advance.