Societies that set norms restraining opportunistic behavior can escape the tragedy of commons and sustain cooperation. Strikingly though, in most societies women remain under-represented in institutions that enforce social norms. For example, women represent less than 20 percent of judges in the Supreme Court and 12 percent of police force in the United States. This differences are even larger in developing countries. This paper investigates the supply side factors that affect the willingness to act as a ‘hired gun’ or delegated party that sanctions bad behavior. We consider the origin of such differences and find that nurture as opposed to nature explain the gender gap. In the matrilineal Khasi tribes women are more willing to enforce social norms than men while the opposite is true in the patriarchal Santal Tribes in India. Our results indicate that changes in the institutional environment can promote gender equity. In particular, anonymity and reduced retaliation possibilities close the gender gap in the willingness to act as the hired gun”.