Reference Re Residential Tenancies Act (Ontario), [1981] 1 S.C.R.

Justice Dickson, writing for the majority, suggested the test.

In this case, it was determined that Ontario's Residential Tenancies Act was not valid provincial legislation.

The test was later applied in Massey Ferguson Industries v. Govt.

413, and eventually modified in Sobeys Stores v. Yeomans, [1989] 1 S.C.R.