Are you wondering if marrying your brother or brother-in-law in Canada is legal? This article will also determine whether you can marry your sister or your wife’s sister.

Why are we writing about it? Because people keep searching for it online!

While navigating family, love, and interpersonal relationships, one may face ethical, moral, and, yes, legal questions. The question” Is it legal to marry your brother in Canada?” touches on one such difficulty. The answer is a resounding “no.”

Prohibited degrees of consanguinity

Put clearly, Canadian law prohibits marriage between siblings of any sort (including half-siblings and adopted siblings). This prohibition falls under what is known as “prohibited degrees of consanguinity” in marital law. 

In short, “prohibited degrees of consanguinity” means you cannot marry someone you share ancestors with. This is an essential part of Canada’s marriage regulations, documented in the Marriage (Prohibited Degrees) Act.

The law reflects society’s ethical and moral norms and customs and seeks to prevent the legal recognition of relationships that could lead to potential familial conflict or societal concerns.

It’s important to note that this prohibition is widely used in many countries, including the United States, the United Kingdom, and Australia. In addition to reflecting societal and moral norms, the prohibition prevents potential genetic implications of consanguineous marriages.

Heightened risk of congenital disorders

When close relatives have children, there is a heightened risk of congenital disorders and health problems due to the increased probability of both parents carrying the same harmful genetic variations.

Social and familial implications

In addition to the biological risk, it is critical to recognize the social and familial implications. Close-kin marriages are discouraged as they will lead to conflicts in the familial structure and blur lines around familial roles and relationships.

Legal implications

In the eyes of the law, marriages that fall within the prohibited degrees of consanguinity are considered void. This means the marriage is deemed never to have occurred legally, even if the parties involved were unaware of their familial relationship when they married. Even if the familial relationship is discovered after the fact, the marriage will be annulled and treated as if it never existed in the eyes of the law.

Purpose of the law

Relationships are deeply personal and involve a spectrum of messy feelings. While the law is not a step-for-step playbook that defines love and attraction, it sets boundaries on how emotions can be expressed in legally recognized institutions like marriage.

The purpose of the law is to safeguard society as a whole. Laws balance personal freedom and societal good between individual desires and collective norms. While it might seem that laws about whom you can marry limit personal freedoms, these regulations exist to prevent potential harm and uphold the societal structure we rely on.

What about your brother or sister-in-law?

While it is illegal to marry a personal related lineally (including brother, sister, adopted or blood-related), the act does not prohibit marrying a brother-in-law or sister-in-law. In short, it is not illegal to marry your brother-in-law or sister-in-law under Canadian law.

However, the legal position does not entirely capture the complexity of this question. For instance, it does not address the scenario where one would marry a brother-in-law or sister-in-law following the death of one’s original spouse.

In this case, it could be argued that societal norms may come into play. While Canadian law may not explicitly prohibit marriage, societal attitudes may still create a stigma around such relationships.

Can you marry your wife’s sister?

Now, the question you’ve all been thinking about — “Can you marry your wife’s sister?”. The marriage laws in Canada forbid marriages between close relatives by blood or adoption; that being said, marrying your wife’s sister wouldn’t be considered illegal per se. 

While this marriage is not under the prohibited degrees of consanguinity, it’s important to remember that you can’t be married to two people simultaneously in Canada. As such, you must be divorced from your current wife to marry her sister.

We hope you found this guide on whether it’s legal to marry your brother in Canada useful.