Can Gender Parity Break the Glass Ceiling? Evidence from a Repeated Randomized Experiment

Gender parity in evaluation committees is ineffective and counterproductive to promoting the hiring of women.


Gender quotas are an increasingly popular tool to encourage gender equality and the participation of women in decision-making areas where they have been traditionally underrepresented. Gender quotas in Europe include corporate boards, party lists, and political cabinets. In Spain, the Equality Law passed in 2007 mandated gender parity for all selection committees in the state administration, party lists, public organizations, and related firms. In this paper, the authors examine the impact of recruiting committees’ gender composition on hiring practices.


A female candidate for the Corps of the Spanish Judiciary is less likely to be selected when the selection committee has a greater share of female members, while that committee composition increases male candidates’ likelihood of being selected.

  • Male candidates are 16% more likely to be selected when evaluated by a committee with one female evaluator (men constitute the rest of the committee members) than when evaluated by an all-male committee.
  • Once there is a woman in the committee, additional female evaluators does not alter candidates’ chances much, as long as female evaluators do not become a majority in the committee.  In female-majority committees, male candidates have 34% higher chance of being selected than they do when evaluated by all-male committees. In contrast, female candidates have 17% lower chances when evaluated by female-majority committees than they do when evaluated by all-male committees.
  • Female majority committees tend to overestimate the qualities of male candidates.

In short, the gender composition of evaluation committees is an important determinant of success in public examinations. Having more women on committees actually results in greater success for male candidates and less success for female candidates.


The study is based on the 51 public examinations for appointments to four different Corps of the Spanish Judiciary (notary, judge, prosecutor, and court secretary). The exams took place between 1987 and 2007, and involved 2,467 evaluators and 150,000 candidates. Exams are typically held every 1 or 2 years at a national level. Candidates are randomly assigned to evaluation committees, with approximately 500 candidates per committee. Committees consist of 7 to 10 members, selected from the respective Corps. In 2007, the Spanish Equality Law was passed mandating gender parity in evaluation committee composition.

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