One of the things which stuck with me from my social psychology class in college was a comparison of gender discrimination in hiring practices comparing male interviewers with female interviewers. The take away was that female interviewers were more likely than male interviewers to end up with sexist hiring results. Their were a number of possible justifications given, such as that the women interviewers felt threatened by having another women take their job (they felt like a "token" member of a team), a sort of stereotype threat where the female interviewer held female interviewers to a higher standard (they didn't want to "confirm" negative stereotypes about women), ect.

I will try to find the citation.