UBC-led study finds crime increases in polygamous societies

Over the course of human history, a whopping 85 percent of human societies have permitted polygamy. However, a new University of British Columbia–led study reveals that this practise has contributed to higher levels of crime, violence, poverty, and gender inequality than in societies which institutionalize monogamous marriage.

The study, entitled The Puzzle of Monogamous Marriage published in Philosophical Transactions of the Royal Society, found that polygynous cultures had notably higher levels of rape, kidnapping, murder, assault, robbery, and fraud. The researchers attributed this boost to larger numbers of unmarried men. The shortage of unmarried women intensified the competition for women and resources between men, who often resorted to criminal activity.

According to the study, led by UBC professor Joseph Henrich, monogamous marriage reduces male competition and social problems by allowing for a more equal distribution of female partners. Institutionalized monogamy also helped men shift focus from finding wives to paternal investment. The increase in parental interests results in long-term planning, economic productivity, financial savings, and child investment.

The study also found that monogamous marriage contributed to improvements in child welfare, including reduced rates of child neglect, abuse, death, homicide, and intra-household conflict.

Gender equality also improved in countries where monogamous marriage was institutionalized. Monogamous marriage often preceded democracy and voting rights for women, boosted female influence in household decisions, decreased spousal age differences, and increased the age of first marriage of women.

Polygamy was outlawed in Japan in 1880, in China in 1953, in India (partly) in 1955, and in Nepal in 1963. Polygamy continues to be practiced in parts of Africa, Asia, the Middle East, and North America.

Henrich served as an expert witness for B.C.'s Supreme Court case involving the polygamous community of Bountiful, B.C.

On Monday (January 23), Bountiful religious leader Winston Blackmore testified in court as part of a three-week trial. Blackmore is appealing a ruling by the Canada Revenue Agency that he underestimated his income by $1.5-million over six years.

Blackmore is reportedly the father of more than 80 children. He is also a bishop of the Mormon sect the Fundamentalist Church of Jesus Christ of the Latter Day Saints, which holds polygamy as a tenet of its faith.

Vancouver lawyer Peter Wilson has been assigned as a special new prosecutor to look into potential sexual offences against minors at Bountiful.

Bountiful leaders James Oler and Winston Blackmore were each charged with one count of polygamy in 2009.

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