When the chief executive of the Women’s Institute said last week that she felt the organisation had no choice but to end its 40-year policy of transgender inclusion, she sounded genuinely upset. When asked on Woman’s Hour whether a debate over trans members had been raging inside the organisation this year, Melissa Green was clear that “this hasn’t been a conversation that has dominated”. Much of the pressure, she said, had come from outside the organisation.

The decision followed a similar announcement from Girlguiding the day before, which will now ban trans girls from joining. Both organisations blamed the change on April’s supreme court ruling on the meaning of the word “sex” in the Equality Act 2010, but that’s far from the whole story. Really, it’s about those pressuring organisations on the basis that the case is closed, and exclusion is now legally required – when that is far from the case.

Consider the Guides. The court ruled that “sex” in the Equality Act means “biological sex” (what is, usually, recorded at birth) in contrast to “certificated sex”– which would have meant, for example, that trans women with a gender recognition certificate were considered female under the act. But under-18s have never been able to get gender recognition certificates. This means that whether a “biological” or “certificated” interpretation is adopted is entirely irrelevant to the inclusion of trans girls. Either way, they would have been considered “male” under the act. If they could be lawfully included notwithstanding this before April, they still can be now. Clearly, then, it isn’t a change to statutory interpretation which is at issue here.

So, what has actually happened? Since the supreme court decision, organisations have faced lobbying and legal threats seeking to compel them to exclude trans people. Girlguiding has reportedly faced a legal threat over its longstanding policy of inclusion, while Green said there had been “reference to legal challenge” in communications the WI had received. (In one Mumsnet thread, a user claimed that she was getting her husband to sue the Women’s Institute for sex discrimination against him, in order to force them to exclude trans women.) Sex Matters has filed a claim with the high court to try to force the Hampstead ladies’ pond to exclude trans women – even though they recently voted to remain inclusive. The group is also writing to a vast swathe of organisations putting pressure on them to change their policies to be trans-exclusionary because “the law is clear”. But the truth is that the law is as clear as mud on this issue.

The Equality and Human Rights Commission, which rushed out a now-withdrawn “interim update” just nine days after the supreme court ruling, is awaiting judgment from the high court in a challenge against the lawfulness of that guidance. The EHRC had claimed that service providers and employers were now required to exclude, for example, trans women from women’s toilets. Both the Good Law Project, where I am the trans rights lead, and the equalities minister, Bridget Phillipson, argued that this was wrong and that organisations could remain inclusive. Meanwhile, the government is still considering the EHRC’s guidance, which must be approved by Phillipson before it is put to parliament.

The Equality Act potentially permits organisations to operate on a trans-exclusionary basis, providing this can be justified, but it does not require it. And there are multiple ways under the act that an organisation may justify operating on a trans-inclusionary basis. A decision of an employment tribunal in Scotland last week ruled that Leonardo UK’s trans-inclusive toilet policy did not place biological women at a disadvantage, and was a proportionate means of achieving an inclusive workplace. In another tribunal decision this week, the judge said a trans woman using female-only facilities “may be lawful” under the Equality Act.

Does it even matter what the law actually says? As a lawyer, I would hope so. But in reality, frightened of being sued, I can see how organisations would be tempted to capitulate – especially when they think the legal threats are all coming from one side. It doesn’t matter if they would eventually win in court – the question is whether they can justify the risk, and the potentially destructive cost of litigation against them. When that organisation is a charity, trustees are placed in an even more difficult position, and will be scared of what view the Charity Commission might take if you decide to fight back.

But it’s unlikely that litigation will only come from one side. Trans people are protected by discrimination law, too, and as organisations start to realise that they were mis-sold on the implications of the supreme court judgment, many will see that they have been led astray. We are also still realising the full extent of the human rights implications, which will become clearer, not just for trans people, but also for women’s rights to freedom of association under article 11 of the Human Rights Act. These issues will come back to bite both organisations and the government if they are not urgently addressed.

What last week has shown is that, despite their hopes to the contrary, anti-trans campaigners have not won the hearts and minds they hoped the supreme court would give them. The response to these decisions from those inside and outside the organisations shows how many people want to remain trans inclusive, and are looking for ways to continue to be so. The pressure on organisations looking to stay trans inclusive is immense – the hope is that they will capitulate, and that this will cause a domino effect of smaller organisations which feel like they have no chance of fighting back.

But this is a moment that requires bravery in standing up for what is right. Organisations that value trans people should know not just that the law is on their side – but so, also, are many people who will step up to defend them if they have the courage to take a stand.

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