In my recollection, there were some court cases in the early 1980s of people refusing to fill out the census—the long-form portion—because it was a sample. Under the old act, there was potential for that to be contentious. Under the proposed amendments, that would no longer be the case. It would be clear that any survey—and that includes the long-form census, which doesn't go to the whole population—can be designated as mandatory by the chief statistician.
On May 4th, 2017. See this statement in context.