[6] Stonewall diversified into policy development after Labour came to power in 1997, a period which saw successful campaigns to: repeal Section 28, end the ban on LGBT people in the armed forces, equalise the age of consent, extend adoption and IVF rights to same-sex couples, and introduce civil partnerships.

The scheme engaged employers in developing best practice and within 18 months successfully garnered members ranging from major banks, through national retailers to Government departments such as the MoD, Home Office and the Treasury.

They asked Stonewall to arrange legal representation, leading to a long battle through the courts with Graham Grady and John Beckett also joining the case.

The judgment of the court was a vindication of the rights of lesbians and gay men and the New Labour government of the time immediately announced that the ban would be lifted.

[26] Stonewall has also produced research reports in areas such as homophobic hate crime, lesbian health and homophobia in football.

[35][36] Members of the scheme are given advice on words and phrases used in their staff support materials, including a preference for gender-neutral language.

[24] Organisations now engaged in the programme, between them employing over four million people include many UK universities[41] health trusts[42] banks and financial institutions.

This was dismissed by the High Court in 2021, with Mr Justice Cavanagh saying: "There is no basis for asserting that the individual prosecutor will be influenced in any way by the CPS' status as a Diversity Champion.

"[44] In May 2021, the Equality and Human Rights Commission (EHRC) announced that it would be withdrawing from the Diversity Champions programme on the grounds that it did not constitute the best value for money.

[49][50] In response, Stonewall argued that the advice was based on the EHRC Code of Practice which had been upheld by a court decision earlier that month.

[57] Stonewall responded that the exit was a result of "organised attacks on workplace inclusion that extend far beyond" the Diversity Champions scheme.

[57] By 2021, several organisations like Channel 4, the Ministry of Justice, United Kingdom, Department of Health, Ofcom and Cabinet Office also withdrew from the Diversity Champion scheme.

[64] In March 2024, a spokesperson for the Scottish Parliament said their membership of Stonewall's Diversity Champions scheme expired in February 2024 and that it would not be renewed.

"[66] Days before the May 2015 UK general election Stonewall apologised after being criticised for publishing an online campaign graphic which suggested that only the Labour Party substantially supported LGBT equality in its manifesto.

[67] Lib Dem Minister Stephen Williams had previously told PinkNews: "I'm astounded by this grossly misleading graphic.

[68] The charity had attracted much attention when it announced in The Daily Telegraph that Stonewall would not be joining the wide boycott of the London hotel where it was to hold a gala dinner.

[citation needed] Stonewall under the leadership of Ben Summerskill came under criticism in September 2010, after he made comments at a Liberal Democrat party conference fringe event that Stonewall "expressed and expresses no view" on same-sex marriage and that the equal marriage policy proposed by gay Liberal Democrat MP Stephen Williams could potentially cost £5 billion.

[77] In 2008, transgender rights activists picketed the Stonewall Awards in protest of the nomination of The Guardian contributor Julie Bindel for Journalist of the Year,[78] who had written a piece in 2004 entitled "Gender Benders Beware" asserting that sex reassignment surgery was "unnecessary mutilation".

"[78] In 2010, The Sun journalist Bill Leckie was nominated for the same award for his column on gay rugby player Gareth Thomas, in spite of being criticised in a Stonewall Scotland report in 2007 for his comments regarding a drag queen bingo night.

[13] In her first interview as incoming chief executive of Stonewall, Kelley argued that the organisation did not need to convince people to agree on a shared understanding of gender, and would instead focus on building support for "changes that make trans lives easier", such as "lower levels of hate crime, better access to health services and more inclusive schools and workplaces".

"[92][93] In November 2021, Kelley spoke alongside "gender critical" barrister Naomi Cunningham and evangelical Christian campaigner Jayne Ozanne in a discussion on "Banning Conversion Practices: The Path to Good Law" during an event organised by the Middle Temple LGBTQ+ Forum.

[96] Writing in praise of Stonewall in The Spectator, James Kirkup, director of the Social Market Foundation, described Kelley's appearance at the Middle Temple event and her live interview with Emma Barnett on Woman's Hour as signals of a decision by Stonewall to engage in conversation, and that both are "laudable things to do and entail no small courage".

[14][19] Subsequently, the chair of trustees, Iain Anderson, called on all participants in the debate on transgender rights to "lower the temperature".

[101] Lesbian barrister Allison Bailey, who helped establish the organisation, initiated legal action against Stonewall in July 2020, claiming she had been victimised as a result.

[107] Writing in The Times, Stonewall co-founder and former Conservative MP Matthew Parris criticised the charity for getting "tangled up in the trans issue" and being "cornered into an extreme stance".