So you snore a little and your spouse has you sleeping in a separate bedroom. That’s your business, right? Maybe not.

The state of your marriage or your common-law status is the government’s business as well because of the tax advantages you might get from being married or, conversely, the deductions you might be able to keep by saying you’re still single.

Expanding income splitting for families, something seniors have been able to do with pensions since 2007, could bring the government into your bedroom like never before.

It’s not like the Canada Revenue Agency and the courts haven’t been there previously. Case law on the subject goes back as far as 1980, with one particular court decision often cited because it outlines key criteria for defining what constitutes a common-law or marital relationship.

That decision — in which the judge decided to provide guidance into what could be considered cohabitation in a marriage-like or conjugal relationship — included a general list that pointed to shelter, sexual and personal behaviour, services performed like meal preparation, social activities together, economic support and what is happening with any children involved.

Living together and sharing expenses is not enough. You have to have a relationship

“People claiming something they are not run the risk of the CRA sending a detailed questionnaire which will ask questions based on all of the criteria,” said lawyer Robert Kepes, of Morris Kepes Winters LLP.  He has had clients who have been sent such a questionnaire but it has been focused on people claiming to be living “separate and apart” in the same house.

“Living together and sharing expenses is not enough. You have to have a relationship,” said Mr. Kepes. “I think a judge will look at all of them and see whether you tip the scales in terms of all of the criteria.”

Just because you sleep together in the same room doesn’t mean you won’t meet the criteria of being married. Mr. Kepes says he knows married people who don’t sleep in the same room. “They had to get a second room for a husband because he snores so badly,” he says.

More than a few couples might fail the part of the relationship test that asks if they eat their meals together but might score points for buying gifts for each other on special occasions.

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