The arrest of an Olympic gold medalist on charges of domestic violence would normally be an occasion for a soul-searching conversation about machismo in sports, toxic masculinity and violence against women. But not when the alleged offender is a woman: 32-year-old Hope Solo, goalkeeper of the U.S. women’s soccer team, who is facing charges of assaulting her sister and 17-year-old nephew in a drunken, violent outburst. While the outcome of the case is far from clear, this is an occasion for conversation about a rarely acknowledged fact: family violence is not necessarily a gender issue, and women—like singer Beyoncé Knowles’ sister Solange, who attacked her brother-in-law, the rapper Jay Z, in a notorious recent incident caught on video—are not always its innocent victims.

Male violence against women and girls has been the focus of heightened attention since Eliot Rodger’s horrific rampage in California last month, driven at least partly by his rage at women. Many people argue that even far less extreme forms of gender-related violence are both a product and a weapon of deeply ingrained cultural misogyny. Meanwhile, the men’s rights activists also brought into the spotlight by Rodger’s killing spree defend another perspective—one that, in this case, is backed by a surprising amount of evidence from both research and current events: that violence is best understood as a human problem whose gender dynamics are much more complex than commonly understood.

There is little dispute that men commit far more violent acts than women. According to FBI data on crime in the U.S., they account for some 90% of known murderers. And a study published in American Society of Criminology finds that men account for nearly 80% of all violent offenders reported in crime surveys, despite a substantial narrowing of the gap since the 1970s. But, whatever explains the higher levels of male violence—biology, culture or both—the indisputable fact is that it’s directed primarily at other males: in 2010, men were the victims in almost four out of five homicides and almost two-thirds of robberies and non-domestic aggravated assaults. Family and intimate relationships—the one area feminists often identify as a key battleground in the war on women—are also an area in which women are most likely to be violent, and not just in response to male aggression but toward children, elders, female relatives or partners, and non-violent men, according to a study published in the Journal of Family Violence.

Last April, when Connecticut high school student Maren Sanchez was stabbed to death by her a classmate allegedly because she refused to go to the prom with him, feminist writer Soraya Chemaly asserted that such tragedies were the result of “pervasive, violently maintained, gender hierarchy,” male entitlement, and societal “contempt for the lives of girls and women.” But what, then, explains another stabbing death in Connecticut two months earlier—that of 25-year-old David Vazquez, whose girlfriend reportedly shouted, “If I can’t have you, no one can!” before plunging a knife into his chest shortly after Vazquez said he was leaving her for a former girlfriend? Or the actions of a 22-year-old former student at New York’s Hofstra University who pleaded guilty last November to killing her boyfriend by deliberately hitting him with her car due to a dispute about another woman? Or the actions of the Florida woman who killed her ex-partner’s 2-year-old daughter and tried to kill the woman’s 10-year-old son last month shortly after their breakup?

Research showing that women are often aggressors in domestic violence has been causing controversy for almost 40 years, ever since the 1975 National Family Violence Survey by sociologists Murray Straus and Richard Gelles of the Family Research Laboratory at the University of New Hampshire found that women were just as likely as men to report hitting a spouse and men were just as likely as women to report getting hit. The researchers initially assumed that, at least in cases of mutual violence, the women were defending themselves or retaliating. But when subsequent surveys asked who struck first, it turned out that women were as likely as men to initiate violence—a finding confirmed by more than 200 studies of intimate violence. In a 2010 review essay in the journal Partner Abuse, Straus concludes that women’s motives for domestic violence are often similar to men’s, ranging from anger to coercive control.

Critics have argued that the survey format used in most family violence studies, the Conflict Tactics Scale, is flawed and likely to miss some of the worst assaults on women—especially post-separation attacks. Yet two major studies using a different methodology—the 2000 National Violence Against Women Survey by the National Institute of Justice and the Centers for Disease Control National Intimate Partner and Sexual Violence Survey published last February—have also found that some 40% of those reporting serious partner violence in the past year are men. (Both studies show a much larger gender gap in lifetime reports of partner violence; one possible explanation for this discrepancy is that men may be more likely to let such experiences fade from memory over time since they have less cultural support for seeing themselves as victims, particularly of female violence.)

Violence by women causes less harm due to obvious differences in size and strength, but it is by no means harmless. Women may use weapons, from knives to household objects—including highly dangerous ones such as boiling water—to neutralize their disadvantage, and men may be held back by cultural prohibitions on using force toward a woman even in self-defense. In his 2010 review, Straus concludes that in various studies, men account for 12% to 40% of those injured in heterosexual couple violence. Men also make up about 30% of intimate homicide victims—not counting cases in which women kill in self-defense. And women are at least as likely as men to kill their children—more so if one counts killings of newborns—and account for more than half of child maltreatment perpetrators.

What about same-sex violence? The February CDC study found that, over their lifetime, 44% of lesbians had been physically assaulted by a partner (more than two-thirds of them only by women), compared to 35% of straight women, 26% of gay men, and 29% of straight men. While these figures suggest that women are somewhat less likely than men to commit partner violence, they also show a fairly small gap. The findings are consistent with other evidence that same-sex relationships are no less violent than heterosexual ones.

For the most part, feminists’ reactions to reports of female violence toward men have ranged from dismissal to outright hostility. Straus chronicles a troubling history of attempts to suppress research on the subject, including intimidation of heretical scholars of both sexes and tendentious interpretation of the data to portray women’s violence as defensive. In the early 1990s, when laws mandating arrest in domestic violence resulted in a spike of dual arrests and arrests of women, battered women’s advocates complained that the laws were “backfiring on victims,” claiming that women were being punished for lashing back at their abusers. Several years ago in Maryland, the director and several staffers of a local domestic violence crisis center walked out of a meeting in protest of the showing of a news segment about male victims of family violence. Women who have written about female violence, such as Patricia Pearson, author of the 1997 book When She Was Bad: Violent Women and the Myth of Innocence, have often been accused of colluding with an anti-female backlash.

But this woman-as-victim bias is at odds with the feminist emphasis on equality of the sexes. If we want our culture to recognize women’s capacity for leadership and competition, it is hypocritical to deny or downplay women’s capacity for aggression and even evil. We cannot argue that biology should not keep women from being soldiers while treating women as fragile and harmless in domestic battles. Traditional stereotypes both of female weakness and female innocence have led to double standards that often cause women’s violence—especially against men—to be trivialized, excused, or even (like Solange’s assault on Jay Z) treated as humorous. Today, simplistic feminist assumptions about male power and female oppression effectively perpetuate those stereotypes. It is time to see women as fully human—which includes the dark side of humanity.

Cathy Young is a contributing editor at Reason magazine.

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