Those are general principles. Most of the time, general principles are found in the preamble of an act, where its objectives are defined. I've never really thought about this.
Mr. Beaulac's case was interesting. He was a francophone from Quebec who lived and worked in British Columbia. Of course, he worked there in English. He asked that legal proceedings take place in French, since he was a francophone. The court asked him, since he understood English, why it should bother to find a bilingual judge, the services of bilingual clerks and so on. That was the gist of the problem.
A fourth trial was ordered. The issue was whether that trial should be annulled because of what British Columbia anglophones considered a procedural irregularity. We maintained that this was not a procedural irregularity but a fundamental right, and that if there had to be a fourth trial, then there would be a fourth trial. It was the only way to stop things.