Can Women be as Violent as Men?

Gender equality meets bank robbery.

Posted May 14, 2015

Gender equality is making strides in most occupations, including violent ones such as the military and police. If violent crime is a “job,” as Woody Allen referred to bank robbery in Take the Money and Run, can we expect to see gender equality there also?

Gender Differences in Violent Crime

As a rule of thumb, men are responsible for over 90 percent of serious violent crimes, such as assaults, homicides, and violent robberies. Why is there such a large gender gap and is it likely to persist?

One might imagine that lower violent crime rates for women reflects a generally lower level of aggression. Yet, marriage researchers observe the opposite pattern. Women are more likely to pick fights with their husbands, they are quicker to escalate verbal aggression, and are as likely to use physical aggression as men (1).

Despite these counter-intuitive findings, men are much more likely to be convicted of domestic-violence-related charges. One obvious reason for this is that men are generally larger and stronger, and may have more experience with physical aggression, such as that commonly associated with contact sports.

Another intriguing difference between men and women in the context of domestic disputes is that men generally become more physiologically aroused in terms of increased blood pressure (2).

If the body is revved up for action, damaging aggression is more likely. Moreover, when it occurs, the aggression is more likely to be extreme, uncontrolled, or “disinhibited,” words that are sometimes used to describe the orgy of violence in unusually grisly crimes of violence.

In the vast majority of such crimes, the perpetrators are men.

Violent Crime as Male-Male Competition

Physical strength is clearly one risk factor for committing violent crimes and this helps explain why so many of the perpetrators are men. Indeed, men's greater average upper-body strength (and height) may have evolved as adaptations for fighting strength (3) although arm strength also contributes to successful hunting of large game that is a male specialization in pre-agricultural societies.

Men make up the great bulk of combatants in warfare that is another possible reason for the evolution of masculine muscular strength, although this is controversial.

Although men are much more likely to perpetrate violent crimes, societies with an excess of women in the population have higher crime rates because there is more extra-marital sexuality and greater male-male competition over sex partners (rather than brides, 4).

In the past, female involvement in organized crime was minimal and largely due to association with gangster husbands or boyfriends. All that is changing and women are beginning to claim a slice of the action as gender equality moves into violent crime as well as other high-risk occupations..

Women of the Future

Modern women are behaving much more like men when it comes to risk-taking and aggression. One sign of this phenomenon is greater participation in contact sports and dangerous competitions such as horse racing or car racing. According to Anthropologist Elizabeth Cashdan (5), in societies where women compete more amongst each other whether in occupations, or over spouses, their levels of stress hormones and testosterone increase.

In the modern world, there are far more women driving on the roads and they drive more aggressively and dangerously than ever before. As a result, their accident rates have risen from very low levels and young women are almost as dangerous on the roads as young men whose aggression and recklessness make driving much more dangerous for everyone else. Small wonder then that women are showing up in previously all-male crimes such as violent bank robbery.

As women have begun to take leadership positions in large corporations, they have also acted as leaders in criminal enterprises. One of the most successful Latin American drug kingpins was a Colombian woman, Griselda Bianco, known as La Madrina, who ran an extensive U.S. operation from Miami. She is not the only woman to rise to the top in organized crime.

That there are female equivalents of Pablo Escobar is intriguing from the perspective of gender differences in violence. Yet, there have always been female sociopaths, just fewer of them than males. Such figures certainly challenge gender stereotypes.

Yet, most evolutionary psychologists would predict that even amongst the restricted population of violent criminals, females will continue to be less extremely violent. The reason is that women remain generally less violent and more risk-averse than men. This risk aversion is tied to an evolutionary past in which women did most of the childcare and avoided violence as a way of staying alive to protect their children.

That theory has already failed in respect to vanishing gender differences in traffic accidents. We should not be too shocked if more women also take up bank robbery, and other violent crimes, as their “job.”


1. Arriaga, X. B., and Oskamp, S., Eds. (1999). Violence in intimate relationships. London: Sage.

2. Gottman, J. M., and Levenson, R. W. (1988). The social psychophysiology of marriage. In P. Moller and M. A. Fitzpatrick, Eds., Perspectives on marital interaction. Clevedon, England: Multilingual Matters.

3. Barber, N. (2002). The science of romance. Buffalo, NY: Prometheus.

4. Barber, N. (2009). Countries with fewer males have more violent crime: Marriage markets and mating aggression. Aggressive Behavior, 35, 49-56.

5. Cashdan, E. (2008). Waist-to-hip ratios across cultures: Trade-offs between androgen- and estrogen-dependent traits. Current Anthropology, 49, 1099-1107.