This is not good news.
Some might find this a trivial technical matter, but it's really not. Having access to good population information is critical for legislators, and having good access to bad information makes it far easier for governments to manipulate the information we do have.
It's well known in sampling literature that people with low income and lower education have lower response rates than those with higher income and higher education. So making it voluntary to fill out the census is perverse, in that the lower income/educated citizens will be systematically under-sampled, and when law makers craft new legislation, when R&D considers market trends, when NGO's analyze planned policies, the impact in that segment of society will be unknown. Or rather, the result won't be an accurate appraisal of what will happen.
Consider this, the census is the only data Canadians have access to on aboriginal academic achievement. How will we be able to make objective assessments of policy alternatives?
All sample surveys that are not mandatory have bias, but it can be corrected, if you know what the true population distribution is. When you have a complete census, you know what the distribution is. So it's really shooting Statistics Canada in the foot by hamstringing what data they have.
This really is an assault on democracy, but because of the poor statistical/mathematical understanding of Canadians, this won't get turned into the issue that it needs to be. At least not by Joe and Jane Public.
The government tries to frame this issue by relating it to privacy concerns. The truth is, that the researchers who use this data never see it. They send their estimation codes to StatsCan, just like the recent HST model simulations in BC. StatsCan just runs the inputs the researchers are interested in, and gives them the results. At no time would anyone see the actual data, except for the professionals at StatsCan.
Basically, the census form is no more an invasion of privacy than is filing a tax return. Anyone who has dealt with StatsCan knows that they are compulsively obsessive about protecting this information. It's almost annoying how protective they can be.
If you still think this is not a big issue, consider this. Canada has a well-known productivity gap. I've yet to read of a single economist that doesn't think that Canada needs to make improvements that address the knowledge sector of our economy. That is where countries with good productivity are making those gains. If we don't have good population data, we don't have good access to good data, and we make it more difficult for:
So basically everyone involved in the knowledge economy.
This decision was obviously made without consultation from the relevant stakeholders in the Canadian public. It also represents further movement towards secrecy in Ottawa, despite pontification to the likewise.
This was actually tried before, by Brian Mulroney. The backlash from the business community was severe. That put the kibosh to that plan. Let's hope that good sense prevails again.