Most law firms are unaware of which diversity initiatives actually work, still misunderstanding what the best strategies are for a more inclusive environment, research has found.

The research, curated as a joint venture project between Thomson Reuters Transforming Women's Leadership in Law (TWLL) and legal research platform Acritas, collected results from 40 big London law firms. The firms were asked which initiatives they believe to be the most effective for gender diversity. The results were then compared alongside which initiatives the research found to be the most effective in practice.

The study found that law firms perceive the most successful approaches to improving diversity to be: flexible working (53 percent), career path support (31 percent), setting the tone of diversity from the top (31 percent), female role models (25 percent), career path transparency (19 percent), and challenging bias (17 percent).

The percentage refers to the percentage of law firms that said they thought it was successful.

However, when testing the initiatives for effectiveness, the research found different levers to be the most impactful. These included ensuring gender diversity in matter teams, ensuring gender diversity in pitch teams and pitch documents, implementing unconscious bias training, and dealing with bad behaviours, such as #MeToo.

Firms with gender balanced teams had a 23 percent higher female retention rate than those that did not. Firms with gender diversity in pitch teams and pitch documents had a 9 percent higher rate, while the rate was 8 percent higher for firms that implemented enforced unconscious bias training. Firms that dealt with bad behaviours had a 4 percent higher female retention rate. 

Retention rate in these cases refers to retention from junior associate to equity partner.

Thomson Reuters managing director Lucinda Case and Acritas chief executive Lisa Hart Shepherd said the running theme appeared to be that instead of mentoring women to do better, law firms should respect their abilities and put them in more top roles.

Case said: "Lower-performing firms are likely to use mentoring. It's not that we think mentoring is bad, but it's not working as effectively as it could be. Another question was: do men respond better to mentoring than women? Because it could quite easily be perceived by women as patronising or pushing them further into silos."

Hart Shepherd added that while flexible working is good, firms again need to be careful to implement in the right way. She said: "Some firms tend to have just women using flexible working, so maybe a suggestion could be that those firms offer male lawyers flexible working to reduce those silos, or enforce a standardised strategy for flexible working across all employees."

She added: "The initiatives that proved to be effective were the ones that ensured women got fair opportunity to build up experience and relationships through mandating mixed-gender matter and pitch teams. And removing bias was of course essential to create the right culture for women to be treated equally."

Reflecting on recent pressures from GCs for law firms to improve diversity, including the recent news that 65 GCs had signed a letter calling law firms to do better, the research found that two thirds of firms perceive client pressure to be having an impact.

The research also found that only 44% of firms set gender diversity targets.