Is the Mansfield Rule moving the needle for women and minorities?

Abstract

Abstract In 2016, inspired by the NFL’s Rooney Rule, the Mansfield Rule was devised to push soft affirmative action policies, including the so-called 30% rule, to incentivize law firms to affirmatively consider women and underrepresented groups for leadership and governance roles, equity partner promotions, and lateral positions. To determine the effectiveness of the Mansfield Rule, I carried out an empirical study that compares those firms that have adopted the Mansfield Rule with law firms that have not. Using a Mann–Whitney Wilcoxon test, I compared the deviation in the demographics, recruitment, attrition, promotion, and committee compositions, including leadership composition, between firms that have been Mansfield-certified, the ‘treatment group’, with the analogous deviation for a ‘comparison–control group’ that did not opt for the Mansfield Rule application. I did so for the years 2007–19. The findings show that the overall population of all law firms and the diversity proportion within the population show an increase from 2007 to 2019, irrespective of the treatment. Furthermore, the treatment had no statistically significant effect on either the growth rate evolution or the predictability of law firms’ behavior related to recruitment, attrition and promotion, and committee composition. These results indicate that applying the Mansfield Rule has no measurable impact on the diversity proportion of the population of the firm, its growth rate, or its predictable behavior related to their firm’s diversity.