WTH are you talking about?
The SCC case, R. v. Khan, is cited in the paper!
As to how the courts have applied R. v. Khan (and there are plenty of cases applying it since 1990), you'll have to do your own research or pay someone to do it for you.
Why do you think the US law on hearsay is significantly different? Here are almost 30 exceptions recognized by category under the Federal rules of evidence:
www.law.cornell.edu
Here's at least a starter to help you understand the growth of a principled approach in the US in conjunction with express exceptions in the Rules of Eviddnce:
en.wikipedia.org
You only found out 10 minutes ago that there were any exceptions. Come back to me when you know something about the subject.