There is a distinction, and you're correct that people are able to make presentations before the Supreme Court, but they know when they do so that they have to make a strategic decision, evaluating whether they can afford to use the language in which they will be more fluent against whether they are going to pay a penalty for doing that because some of the nuance is not going to be understood. That's not the case in the federal courts, where people have the right to be heard and to be understood.
This issue of the right to not only be heard but to be understood is one on which the Supreme Court itself has evolved its own view of the right to a trial in French. In the Société des Acadiens case back in the 1980s, I think, the court at that point ruled that one had a right to be heard, but one did not have a right to be understood. Subsequent decisions in the Supreme Court have altered that view.
I will defer to Madame Giguère to explain a bit of the evolution of that Supreme Court position in terms of the right to be understood.