First of all, the tribunal does not collect or charge fees for hearing a case. So the short answer to your question is that it's the government that picks up the tab for the costs of operating the tribunal.
Chair, Office of the Chairman, Canadian International Trade Tribunal
First of all, the tribunal does not collect or charge fees for hearing a case. So the short answer to your question is that it's the government that picks up the tab for the costs of operating the tribunal.
See context to find out what was said next.