Like an undead Glenn Close rising from the bathwater in Fatal Attraction, self-identification of sex fought back at the BBC on Friday with a soiled nappy fetishist and a weapons obsessive in a flying wedge. The BBC’s disordered relationship with self-ID is facing its final battle.

Just at the moment when it has its best opportunity to return to rationality without confessing former sins, the BBC’s pronoun problem is visibly out of control on the website.

'Fetishist dumped soiled nappies at nurseries' from South Shields

'Ex-PCSO jailed for trying to make 3D printer gun' from Lincolnshire

The pieces are about a revolting pervert and a violent misogynist. Abbi Taylor’s crimes are vomitous. Zoe Watts has filmed himself smashing plaster heads of feminists. In each case their sex is in the public domain and relevant to the crime. The BBC calls both of them women via pronoun use. Neither is posted on the trans page. Nowhere is their sex explained.

Wrong, wrong, wrong. The BBC has been consulting on sex and gender reporting for a while and we’ve submitted responses. In the middle of the consultation, the Supreme Court judgement happened. The BBC’s already told us it’s waiting for EHRC guidance on its workplace single sex policy - for example, it’s still allowing trans-identified men to use the women’s toilets in its buildings. That guidance is due to be published quite soon.

So the BBC stands at the edge of an editorial abyss. The results of this consultation will be front page news. And any plan to publish revised editorial guidance which does not throw out self-identification of sex, will go down badly. Retaining female pronouns for trans-identified men would be ferociously unpopular and indefensible, a PR disaster.

Any tweaks around trans status will fade into insignificance compared with the retention of self-identification of sex via preferred pronouns. The reputational damage of the BBC deciding that it’s above the law will be painful.

It has to decide to default to biological sex descriptors. At the moment it defaults to gender identity descriptors. Simply turn that its head, and the work is done.

This wouldn't mean a mandate to always use biological sex terms, though obviously we think that would be best. Such a move would have exactly the same level of prescription as the current guidance to default to self-identified sex 'unless there are editorial reasons' - except the BBC would be defaulting to legal and scientific reality.

It's objectively inaccurate to describe Watts and Taylor as women, which is reason enough not to do so. But let’s make a wild value judgement too - it's disgusting to comply with these mens' wishes and it makes the BBC look outdated and irrelevant. There is not one reason to comply.

So how will the BBC justify it when asked? This we know - because it does it all the time - it will simply say ‘It’s in the Style guide. That’s what we do’. That’s how easy it is, and it repeats it through every stage of the BBC process.

It could just as easily say the same thing to gender identity activists complaining about accuracy. ‘It’s in the style guide. That’s what we do’. It really is that straightforward.

So far we’ve seen guideline chaos as BBC regions begin efforts to shift their stance. The piece about Zoe Watts calls him a transgender woman (falsely - he's a transgender man), then deletes the phrase - why? Because it called him trans? Because it called him a type of woman? It’s live action activism and arguments behind the scenes. At no point does the piece explain that Zoe Watts is a man. In the Abbi Taylor story there's clearly an effort to avoid pronouns but ultimately the online reporter gives in and calls him a woman several times. Again, it doesn't explain he's a man. There are no fact checks. The tagging is wrong and clearly no reporters have asked the police for additional clarity or their own lawyers to check restrictions.

There is nothing wrong with using 'he' and 'him' and stating the whole male truth. There's no law against it. There's no regulatory prohibition.

The only problem with it is the likely activist 'backlash' to a bio sex default. But why would the BBC defer to that? It's a rationale that's tough to defend. The standard form - ‘that’s just what we do’ - won’t be available. There’ll have to be a substantive defence for refusing to tell the audience that disgusting male criminals are men.

The BBC adopted self-ID on the basis that 'innocent' people deserve it. Self-ID is then carried across to criminals and sex offenders as an implicit acknowledgment that it cannot devise a 'sliding scale' of self-identification merit.

In the same way, it can't selectively adopt bio sex descriptors only for criminal offenders - which might be an approach the BBC would see as a middle way.

Which offenders? How serious must the crime be? What about transgender males who engage in the debate on competing rights - shouldn’t their sex be accurately described too? What if they’re perverts but not criminal perverts? What if they’re workplace bullies or spouses or parents, now getting affirmed on national TV?

Every man who claims to be a woman will still come into contact with women every day in his personal, professional or public life. Any of these women may have suffered misogynistic violence or trauma. The BBC can't possibly select whether and which transgender males deserve national, publicly funded deference to their wishes at the expense of every other cohort in society.

Would it be planning to produce criteria? Or to devote a member of staff to be permanently on standby to judge whether a particular person has earned the right to self-ID? Will it share those judgements with the Complaints Unit, who’ll have to publish them in responses? Wouldn’t it rather end the problem here and now with a clear decision based on its core principles of trust and accuracy?

The concept of selective self-ID is unworkable and impossible. The BBC is going to be accused of transphobia anyway if it adopts it, it might as well take the much more defensible position of defaulting to universal accuracy. Hung for a sheep as a lamb and so on. Existing activism within the BBC (especially the regions, which has never been dealt with, and from where all these stories are retched) means nuance isn’t possible. Any attempt at a middle way will default to self-identification.

The BBC now has to at minimum default to bio sex pronouns. There are ways, other than looking, of finding out what sex people are. And making a media inquiry to the police about it isn’t illegal. Every single story involving a trans person needs a trans tag: each needs links and hyperlinks to fact checks about the reality of sex. Historical content should be revised, edited, or removed. Guests - yes, including celebrity guests - need to be told there’s no more hiding behind the ‘trans’ label - the audience is going to be told what sex you are

Self-identification is incredibly harmful to women, children and LGB people. The BBC can't go along with that harm any longer. The retention of conditional self-ID might be hoped for as a compromise, but it won't be seen as one, because it won’t be one. The presumption will still be self-ID unless you’re prosecuted, tried, convicted and sentenced, and even then not for all crimes, and even then you still don’t get called a man. That’s self-identification, there’s no pretending otherwise.

Retaining self-ID will throw away a one-time opportunity and be devastating for the BBC. Over at Seen in Journalism we have bottomless depths of advice on how to write stories without using inaccurate sex pronouns, while remaining within the law and regulatory observance. It's not hard.

The CEO of BBC News once suggested that dropping self-ID would be like detonating a landmine under the newsroom. Now, it’s the other way around. At this moment, the BBC has an opportunity to change its guidance without admitting past fault. The updated EHRC guidance will confirm what the law says: that the people the BBC calls 'trans women' and 'she/her' are men, under the law as well as in reality. It will be lamentable and unjust if the BBC insists on continuing to tell its audience that they're women, but it certainly won’t make the problem go away. There’s only one way to do that. Recover the lost art of sexed language. Bring back accuracy.