This paper studies whether the gender composition of recruiting committees matters. We make use of the unique evidence provided by Spanish public examinations, where the allocation of candidates to evaluating committees is random. We analyse how the chances of success of 150,000 female and male candidates for positions in the four main Corps of the Spanish Judiciary from 1987 to 2007 were affected by the gender composition of their evaluation committee. We find that a female (male) candidate is significantly less likely to be hired whenever she (he) is randomly assigned to a committee where the share of female (male) evaluators is relatively greater. Evidence from multiple choice tests suggests that this is due to the fact that female majority committees overestimate the quality of male candidates.