Women are underrepresented in many prestigious positions. Could increasing the share of women in hiring committees boost the rates at which women are hired into these positions? I use a difference-in-differences design to examine the effects of a French law on academic hiring committees that required each gender to represent a share of at least 40% of members. Contrary to the objectives of the law, I show that the reform backfired and significantly lowered women's probability of being hired. Because the negative effect of the reform is concentrated in committees headed by men, this result seems driven by the reaction of men to the reform. I find little evidence that the reform affects supplyside characteristics, such as the likelihood of women applying. The results suggest that the underrepresentation of women is unlikely to be solved by simply increasing the share of women in hiring committees or interview panels.