Launched last summer as a corrective to an industry dominated by white men, the Mansfield Rule sought to tackle the gender and diversity gap in Big Law leadership in part by using a powerful promise: bragging rights.

Now, 41 of the nearly 50 firms that implemented the rule in its inaugural pilot year have earned those rights, receiving the coveted designation, “Mansfield Certified.”

“Law firms are not typically early adopters on risky endeavors, especially ones where the results will be made public,” said Caren Ulrich Stacy, CEO of the Diversity Lab, which worked with the firms to implement the Mansfield Rule.

“But these 41 firms showed their true desire to boost diversity in leadership by trying something new and tough to implement,” she said.

Adopted from the National Football League's Rooney Rule, which requires teams to interview at least one minority candidate for general manager or head coaching positions, the Mansfield Rule was developed following the 2016 Women in Law Hackathon.

The rule requires that at least 30 percent of participating law firms' candidate pools for leadership or governance roles—as well as equity partner promotions and senior lateral positions—be comprised of women or minorities.

In its inaugural year, the Diversity Lab collected data and information from law firms at the six-month and one-year mark. It also collected data at the conclusion of the first year of implementation on the firm's current leadership roles, promotions and hiring outcomes to determine certification, Stacy said.

“This is a long-term play, [and] these firms are taking intentional and measured actions to diversify their leadership ranks,” she said.

The law firms that can now call themselves “Mansfield Certified” are: Akerman; Arnold & Porter Kaye Scholer; Blank Rome; Brinks Gilson & Lione; Brownstein Hyatt Farber Schreck; Bryan Cave Leighton Paisner; Buchanan Ingersoll & Rooney; Clifford Chance; Cooley; Covington & Burling; Day Pitney; Dentons; DLA Piper; Dorsey & Whitney; Faegre Baker Daniels; Fasken; Fenwick & West; Fish & Richardson; Goodwin Procter; Holland & Hart; Holland & Knight; Jenner & Block; Katten Muchin Rosenman; Latham & Watkins; Littler Mendelson; McDermott Will & Emery; Miller Canfield Paddock and Stone; Morgan, Lewis & Bockius; Morris, Manning & Martin; Morrison & Foerster; Munger, Tolles & Olson; Nixon Peabody; Orrick Herrington & Sutcliffe; O'Melveny & Myers; Reed Smith; Seyfarth Shaw; Sheppard, Mullin, Richter & Hampton; Troutman Sanders; White & Case; Wilmer Cutler Pickering Hale and Dorr; and Winston & Strawn.

In addition to the incremental increases in diverse candidates considered for some of Big Law's top positions, Diversity Lab also found a significant surge in firms that are now tracking and measuring their candidate pipelines.

Prior to implementing the Mansfield Rule, only 30 percent of the 41 Mansfield Certified firms tracked diversity statistics among their pool of candidates for leadership positions, and an even smaller percentage tracked their lateral hirings for senior associate and partner positions. Now 100 percent of the 41 firms are tracking this information, the data found.

“The Mansfield Rule has really brought a rigor and discipline to the whole process,” said David Koschik, partner and member of White & Case's executive committee.

“It's also caused us to look at situations where we might either not have a female partner or diverse partner in our minds ready for a leadership opportunity [and] it's caused us to look at why that is,” he said.

Koschik also noted that there is an external component to being Mansfield Certified that holds firms publicly accountable to clients and potential clients around the advancement of women and minorities.

Stacy noted that 70 legal departments have asked their current and potential outside counsel if they are certified or are in the process of becoming certified.

Earlier this summer, the Diversity Lab announced Mansfield 2.0, which will broaden the obligation of law firms and expand the rule to include LGBTQ+ attorneys for the 65 law firms that have already signed on.

And while there were a handful of firms that didn't finish the process or meet the requirements to become Mansfield Certified in its inaugural year, Stacy said Diversity Lab will keep working with them.

“Even if firms don't qualify now, participation is encouraged and important because the act of measuring causes improvement,” she said.

It's the firms that haven't made the commitment that have the biggest challenge, Stacy said.

“They have a problem. They know they have a problem. And they still don't do anything about it,” she said.