Canadian family laws, which adapted for common-law and same-sex couples, as well as multiple parents of children conceived using reproductive technologies, may have to adapt once again, according to new research on polyamory.

This summer John-Paul Boyd, executive director of the Canadian National Research Institute for Law and the Family, conducted the first national survey of polyamorous families. Polyamorists are people who choose to commit themselves to more than one committed intimate partner at the same time.

"It's not a huge number of people, but it's still significant and I believe the population is growing," said Boyd.

More than 550 people responded to the survey, which found most of Canada's polyamorists live in B.C. and Ontario, followed by Alberta.

While half of respondents reported having relationships that involved three people, most choose to live in two households. Twenty-three per cent of those surveyed said at least one child lives full-time in their house.

Respondents also reported higher levels of education and income than most Canadians. Yet only one-third of those polyamorists said they had taken legal steps to formalize the rights and responsibilities of everyone in the family.

Polyamory is not polygamy

Unlike polygamist families, which are typically faith-based, patriarchal arrangements where one man marries two or more women, polyamory is legal because no one is married to more than one person at the same time.

Polyamorists further distinguish themselves from polygamists by highlighting that their relationships are consensual and egalitarian.

"Nothing in the Criminal Code stops three or more consenting, informed adults from living together and engaging in a family relationship how and as they please," said Boyd.

Shannon Ouellette says polyamory allows for another choice beyond cheating, serial monogamy or divorce - but legal issues can pose problems. (CBC)

As for why he chose this line of research, Boyd says he grew curious after a number of polyamorous clients approached him for legal help.

"Most people who are involved in polyamorous relationships have executed emergency authorizations to deal with health-care issues. Following that, most people had done school authorizations so other adults could deal with the school on behalf of the kids, followed by legal and medical powers of attorney and things like this," he said.

Yet those measures only go so far. Boyd explains many laws and regulations only accommodate someone with a single married or common-law spouse. For instance in Alberta, the Adult Interdependent Relationships Act clearly sets out that someone may not have more than one common-law partner at the same time.

That hasn't stopped Shannon Ouellette.

Divorce a means to an end?

"About 3½ years ago we made the decision to open up our marriage and we each have additional partners. I have a male partner who lives in England and my husband has a female partner who lives here with us," Ouellette told CBC News at her home in northern Alberta, "There is a choice, other than cheating or serial monogamy and multiple divorces or failed relationships."

However, after two children and 22 years of being happily married, Ouellette and her husband have started talking about divorce as a way to accommodate their new family.

"I don't want to have to divorce my husband in order to marry my partner so that we can be in one country together — but we have discussed it," she said.

But divorce wouldn't solve other legal issues unique to polyamorous families.

"My husband's partner is going to school and we're paying for her schooling and you know we don't get to claim her tuition or books and my husband doesn't get to claim her as a dependent even though we're supporting her," Ouellette said.

And there are other hurdles.

Laws recognize families as 2 adults plus children

"The social service benefits such as health-care arrangements, Canadian Pension Plan, Old Age Security and other benefits, such as employment insurance, that are indexed to the number of people in the household — those laws are also predicated that a relationship consists of two adults plus children," Boyd said. "I imagine at some point we're going to have a charter challenge much like we saw in 2003 with same-sex marriage."

That's unlikely as long as polyamorists remain quiet about their relationships.

"I think more and more people would challenge the charter, ask for more rights and look for more legal protection but the challenge there is that would involve them being out," says Michelle Desrosiers, a married mother of two who is out to her friends, family and work colleagues about being polyamorous.

Michelle Desrosiers of Kitchener, Ont., is in a polyamorous relationship. (CBC)

"My husband has a girlfriend and I am also seeing two other men and they also are married with families as well. So, one big awesome community."

In her experience, Desrosiers says the greatest concerns people have before coming out as polyamorous centre around their children. As many Canadians cannot yet distinguish between polygamy and polyamory, Desrosiers says many in her community fear losing custody of their children.

"A lot of these families have children and they are concerned about being outed and what that means and as long as that fear is in place, there's not going to be a fast push for those legal rights to be changed," she says.

Polyamory and the courts

At least one Canadian court has already recognized the parental rights of polyamorists.

In 2013, a B.C. court settled the case of BDG v CMB, in which a woman who had left a polyamorous family that included the father of her children wanted to move out of province with the kids.

The judge refused and said it was vital for the children "to remain here and not relocate to Alberta so that they can have equal parenting time with both parents and continue their relationship with their siblings and extended family and others who they are bonded with."

No matter how many long-term partners someone has, Boyd says it's always prudently unsexy to prepare for the worst-case scenario.

"Building a relationship agreement would actually help to head off a lot of the problems that people may experience down the road, in the event their relationships go asunder," he says.

Ouellette and her family have talked about drawing up legal documents for worst-case scenarios, such as illness, death or someone leaving the relationships, but Ouellette remains concerned they would remain unprotected.

"It's those moments when we're at our most vulnerable, when somebody is ill or that we're going to struggle the most and at that time we have no rights. The two, three, five years and all the intentions we had to have a life partnership are meaningless."