Twitter has been flooded with controversy for the last week about the RadFem2012 conference, currently booked into the Conway Hall, which announced its membership as restricted to "women born women and living as women" (it originally said "biological women", but that got changed after much mockery). This disturbed the trans community, which it is meant to exclude, but also those feminists who regard trans-exclusion as something other than radical.

To be clear, I know no trans women, still less trans men, who want to spend time in a space organized by people who slander us. However, one of the main speakers at the conference is Sheila Jeffreys, who has a forthcoming book critiquing trans medical care. In much of her earlier writing (see, for example, page 71 of this journal), she calls for "transsexualism" to be declared a human rights violation and then surgery banned by international law, so it's fairly clear that we have an interest in the debate. What Jeffreys proposes has, of course, other implications for all women – the Vatican would love to make similar declarations about reproductive freedom.

There is also, more importantly, the question of whether what Jeffreys and her supporters say about trans people constitutes hate speech. As of two days ago, the Conway Hall expressed their concerns about the legality of trans exclusion, and about hate speech, to the conference organisers.

One of the problems with the Internet is that it is possible for people to lock themselves further and further into a restricted mind set where they hear no other voices. On the other hand, it makes it possible for those with a strong stomach to overturn every stone and find out just what people are saying and thinking. It's clear that Jeffreys and her supporters are very hurt and disappointed that so many younger women don't agree with her – Jeffreys blames the corrupting influence of post-modernism and queer theory; "trans-critical" lawyer Cath Brennan - who uses Twitter to deride trans people's experiences and mock non-trans feminists who are their allies - is also a RadFem2012 attendee.

Of course, the trans issue is only one aspect of the conference. Its mission statement makes it clear that this is a "female-only, activism-focused conference with a radical feminist agenda". Space will not be given to anti-feminist sentiments, which is arguably another way of saying that, on most crucial issues, the party line is predetermined and that any dissent from correct "radical feminist" thinking will be stigmatised and driven out. Jeffreys makes it clear in many of her writings that post-modernism and queer theory are the enemy, and that piercing, tattooing, BDSM and role play are all pollutions of a feminism that is nothing to do with choice or preference, everything to do with commitment. Indeed, the Radical Feminist Hub, to which she contributes regularly, links to resources arguing that what it calls "penis-in-vagina" sex is a bad idea, from which women should choose to refrain.

There are many debates within feminism, and the women's movement ought not to be a monolith of orthodoxy. There are, for example, legitimate arguments on both sides of discussion of sex work – whether the stress should be placed on prohibition or harm reduction, say. But such a debate will not be allowed at RadFem2012. I hate to say this of other feminists, but aspects of their feminism – the anti-intellectualism, emphasis on innate knowledge, fetishisation of tiny ideological differences, heresy hunting, conspiracy theories, rhetorical use of images of disgust, talk of stabs in the back and romantic apocalypticism – smack less of feminism than of a cult.

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