A former race adviser to Boris Johnson who is standing to be Conservative candidate for mayor of London has defended the role of diversity schemes, saying Liz Truss would not be prime minister had it not been for such a scheme. Samuel Kasumu said the Tory party’s “A-list” of priority candidates, championed by then leader David Cameron, was instrumental in catapulting Truss into No 10. In 2006, Cameron promised to transform the Tories with an “A-list” of priority candidates, in an attempt to modernise the party by pushing for women and ethnic minority candidates. The list included Liz Truss, and the former home secretary Priti Patel. “Not everybody loved David Cameron’s ‘A-list,” Kasumu said of the scheme, which was shelved a year later in favour of a general list. “But if it wasn’t for the ‘A-list,’ Liz Truss and a number of others wouldn’t have been elected in 2010.” Kasumu, 35, left Downing Street more than a year ago, after he resigned as Johnson’s special adviser for civil society and communities, in response to the furore over the government’s controversial racial disparity report, which dismissed institutional racism. Having resurfaced from a year-long sabbatical writing a book about his time in No 10, Kasumu last week announced his bid to run as a Conservative candidate for mayor of London. On issues of climate change, the need for more housing, and violent crime, Kasumu said he would be “unapologetic” in his approach. As the only senior black adviser to Johnson before he resigned last April, Kasumu’s loyalty to the party has not been dampened. He acknowledged “bridges need to be built” with the black community, after tPatel described the Black Lives Matter (BLM) protests that swept the UK last year as “dreadful”. Instead of leaving the party, Kasumu decided to try to enact change from within. In August, he co-founded the 2022 Group, an organisation aimed at improving the Conservatives’ “toxic” brand and its relations with the UK’s African-Caribbean communities. “I’m optimistic that the 2022 Group will help to inspire a new generation of people into public life, and we’ll demonstrate that the Tory party is a broad church in every respect,” he said. With a new prime minister and Tory leader, Kwasi Kwarteng as the first black chancellor of any government, Suella Braverman the second British-Indian home secretary, and James Cleverly as foreign secretary, Truss’s new cabinet has been trumpeted as the most diverse cabinet in British history. Of the three female prime ministers to hold office, Truss, 47, is the youngest. “A lot of progress we make across sectors you’ll find that there’s a clear link between age and increase in representation,” Kasumu says, referring to Truss’s youth and the diversity of her cabinet. In her leadership bid against Rishi Sunak, Truss promised to reduce the cost of the civil service by scrapping diversity and inclusion jobs which she said “distract from delivering on the British people’s priorities”. While the Conservatives have generally eschewed all-women short lists, and ethnic minority quotas in favour of meritocracy, Kasumu said diversity schemes were necessary for the upward mobility of underrepresented groups, though he conceded “the way that they’re designed is important”. “The civil service fast stream probably have the most impressive diversity scheme,” he said, referring to its targeting of undergraduates with disabilities, and those from ethnic minority and lower socio-economic backgrounds. The most diverse cabinet in history under a Tory government demanded a fresh approach to inclusivity, Kasumu said, engaging with people from different ethnic minority and class backgrounds, and bringing expertise to the table that comes with hiring people with lived experience. “I would suspect, now that the [leadership] contest is over, people will increasingly become aware of the need to continue to invest in and try to find ways for us to live side by side as one nation, a nation of lots of people that, for many reasons, consider themselves outsiders,” he says.