This letter does that. It talks about the folly of basing a system, when the liberty of Canadians is involved, on unsworn material that is presumed to be reliable but can't be tested and when there is no obligation by the requesting state to show exculpatory evidence.
Let me add this: There's no full disclosure made here. They can pick and choose foreign states. We just trust them to be as honourable as Canadians would be.