In many countries across the globe, polygynous marriages—one man married to more than wife—exist outside the threshold of legality and tolerance. Reality television has brought the question of polygamy’s criminality into the homes of millions of viewers. The best-known is Sister Wives, which began airing in 2010 and documents the life of Kody Brown, his wives—Robyn, Meri, Janelle, and Christine, and their 18 children. Shortly after its debut, police in Lehi, Utah, announced opening an investigation into possible felony charges of bigamy, carrying at that time a possible penalty of twenty years in prison for Kody and up to five years for each wife. In a dramatic final episode of the second season the Brown family fled Utah, moving to Nevada for fear of being charged. People magazine quotes Meri, Kody’s first wife, stating that she views polygamy as “basic human rights, civil rights.”

While some see living in polygamy as a right, others argue that it is a harmful and violent patriarchal family structure that must be criminalized. Awa Ba began an organization—End Polygamy [En finir avec la polygamie]—in France after her sister was subjected to it. For her, forbidding polygamy is necessary to fight the extreme violence that it represents. These opposing ways of understanding polygamy have shaped how governments seek to regulate it. My book, Forbidden Intimacies: Polygamies at the Limits of Western Tolerance, takes a comparative deep dive into the mismatch between what I found to be the existence of polygamies and the ways that governments regulate them as a singular, harmful structure. From 2010 to 2016, I conducted ethnographic research, conducting 145 interviews with 165 participants, to understand how polygamies are lived and how regulation impacts these families in the United States, Canada, France, and Mayotte in the Indian Ocean.

Polygamy is a multidimensional phenomenon, and there is no single reason why it persists even in contexts of illegality. Being a deeply rooted sociocultural practice for some, and being permitted or required in some religions, certainly contributes to its persistence. Still, it is rare globally. According to a Pew Research Center report, roughly 2 percent of the global population lives in polygamous families. It is banned in every country in North and South America. In the United States and Canada, the most visible population is Mormon fundamentalists such as the Brown family, with an estimated 40,000 to 60,000 individuals, living mainly in Utah. In France, polygamy is tied to colonialism and migratory patterns from West Africa in which workers from former colonies brought over multiple wives in large numbers in the 1970s and onwards. An estimated 200,000 individuals live in polygynous households in France. Mayotte became France’s 101st department in 2011 making its inhabitants French citizens. Its traditional practice of polygamy among its Muslim African population has been progressively banned since 2005.

One reason polygamy is forbidden is the problematic way that it puts power into the hands of a patriarch who can exploit his wives. While this kind of power dynamic certainly exists, my research finds that the way that polygamies are lived depends on social context. For example, some polygamies are homegrown, emerging out of the cultures and societies in which they are rooted, and others migratory, being transported into a new national context. The ways that emotions are structured and experienced in polygynous relationships also shape how they are lived. My concept of labyrinthine love helps us understand how types of love, jealousy, and commitment blend together to making some families workable and others not. For some families, there is little love and jealousy leads to violence between wives and sometimes between wives and children. Abdou, the son of a second wife who grew up in the suburbs of Paris, expressed: “In Senegal, we call the other wife my mother’s rival, because for her, she was a rival. So, she took care of me because she had no choice. I was in the house, but she didn’t take care of me [like a mother would].” In other cases where the family works well together, women benefit from having sister wives where they can share working outside the home and household tasks. In Utah, Julie married as a second wife at age 18. She told me: “You come up with your insecure feelings, or your jealous feelings, or your . . . But, in the long run, when it is all said and done, I absolutely love living with Oliver and Ellie. I love sharing our lives together. Love sharing our children.” For families that work well together, jealousy is often dealt with head on.

While polygynous families flourish or self-destruct, governments struggle to regulate them, generally participating in racial projects that define a racialized other based on the specter of polygamy. As the title of the book suggests, governments ban polygamy because it exists at the limits of “western” tolerance. Regulation often pushes these families underground and makes women and children even more vulnerable. A good example is France, where most of the families living in polygynous households have migrated from former colonies. In 1993 the Pasqua law banned living in a polygynous household, and the French government sought to implement a policy where men must “decohabit”—live with only one wife—or lose their ten-year residence permit. One woman I interviewed who worked extensively with these families explained the serious consequences of this policy: “They are obliged to lie, they are obliged to hide, they are obliged to say this, to say that, but none of it is true!” If the goal is to aid women and children in these families, banning polygamy often has the opposite effect.

Forbidden Intimacies is about how intimacy, as a feature of all important relationships, is shaped by what is determined to be intolerable. The book takes the reader on a journey to understand the ways that polygyny becomes antithetical to intimacy itself.

Melanie Heath (@DrMelanieHeath) is Associate Dean of Graduate Studies and Associate Professor of Sociology at McMaster University, Ontario, Canada. Her research focuses on the politics of transformations in gender, sexuality, and family.