Discrimination over jobs is bad. Bad for those discriminated against, and bad for society, as talent is wasted and divisions sown. Women reaching senior leadership positions in organisations is generally a sign of success for gender equality – but it can also lead to increased equality elsewhere. That is the important finding from new research on the (not famously diverse) world of judges. The study looks at the hiring of law clerks by senior judges in the US. Judges have almost total discretion on hiring aspiring lawyers for these prestigious posts, which makes it easy to investigate what might lead to different decisions. It turns out that male judges who have worked alongside female judges are significantly more likely to hire a female law clerk – by four percentage points in the following year. Female judges who have worked alongside female peers are 1.6 percentage points more likely to hire a female law clerk. The authors say that male judges gain a more positive view of women’s “professional capabilities” from working alongside them – a realisation that is understandably a lot less ground-breaking for those same senior female judges… So for all those company leaders out there puzzling over how to diversify the people you hire, the answer is diversify yourselves. • Torsten Bell is chief executive of the Resolution Foundation. Read more at resolutionfoundation.org