It's difficult to imagine how that provision could be saved. There is no precedent in Canadian law. There are lots of situations where people give information to the police anonymously. The law has always protected confidential informers who want to be tipsters and keep their identity anonymous. That privilege is assiduously protected by the courts. But this is talking about giving evidence secretly. There's been no precedent for it in Canadian law and it's difficult to imagine a situation where that would be permissible. Certainly, just saying it's in the best interests of justice doesn't seem to take into account all the concerns here. It's difficult to imagine a way that this provision could be made to be constitutional. It's simply unprecedented.
On October 30th, 2014. See this statement in context.