Canada is protected at the federal level by a piece of legislation called PIPEDA, the Personal Information Protection Electronic Documents Act. It governs the information collection practices of all private businesses within Canada, including financial institutions such as Canadian banks.
There is a laundry list of provisions to protect our privacy rights. Financial information under PIPEDA is considered along with health information to be the most sensitive form of personal information. Banks must keep this confidential under all circumstances.
The IGA overrides that. That's just one example. It also overrides the Privacy Act, the access to basic banking services regulations, and many others.