The Charity Commission has confirmed it is conducting an "ongoing" investigation into the campaign group Sex Matters. The confirmation follows a complaint made to the regulator by Jolyon Maugham KC, founder of the Good Law Project.

Maugham's complaint centred on Sex Matters' decision to platform activist Richard Dunstan, who had made comments speculating about Maugham's childhood experience of sexual assault. In its response to Maugham, seen by the Good Law Project, the Charity Commission stated: "The issues you have raised have been passed to the Regulatory Compliance team to consider as part of our ongoing case into the charity."

Sex Matters, which campaigns on issues of sex and gender and has been publicly supported by author JK Rowling, has not responded to requests for comment on the investigation. The group is not currently a registered charity but operates as a not-for-profit company.

The Good Law Project has previously been involved in legal action concerning the charitable status of groups involved in debates on gender identity. It funded a challenge by the trans youth charity Mermaids against the Charity Commission's decision to register the LGB Alliance as a charity.

In that case, a tribunal found that Mermaids' submission—that the LGB Alliance had "gone beyond the boundaries of civilised debate"—was "well-founded" based on the evidence. However, the challenge ultimately failed because the tribunal panel could not agree on whether Mermaids had the legal standing to bring the case, nor on the final question of whether the LGB Alliance met the legal definition of a charity.

The Charity Commission does not typically comment on the existence or details of ongoing investigations.