Cohabitation greatly increases the risk of child abuse, whether the biological parents are cohabiting or the mother is cohabiting with a boyfriend. Both conditions rank very high on the risk scale, but the environment in which a child lives with the mother's cohabiting boyfriend is by far the worst.
The study Broken Homes and Battered Children by Robert Whelan [Family Education Trust, 1993] found that the incidence of child abuse is 20 times higher for children living with their cohabiting parents and 33 times higher among children living with their mother and her boyfriend compared to children living with their biological, married parents. Similar risks apply in cases of fatal child abuse. The overwhelming number of child deaths occurred in households in which the child's biological mother was cohabiting with someone who was unrelated to the child.
The study, The Child Abuse Crisis: The Disintegration of Marriage, Family and the American Community, [Heritage Foundation, 1997] restates the risk of child abuse being 20 times higher than in traditional married families if parents are cohabiting (as in "common law" marriages) and 33 times higher if the single mother is cohabiting with a boyfriend. This research suggests that cohabitation is a much greater risk factor for domestic violence than marriage because relationship ties tend to be weaker within cohabitation compared with marriage.
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