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Feminism: Sex and gender discussions

Should the UK have a simple, clear legal definition of sex, male and female?

75 replies

SingleSexSpacesInSchools · 30/05/2026 22:09

To follow on from https://www.mumsnet.com/talk/womensrights/5533120-5533120-should-the-gender-recognition-act-be-repealed?page=6&reply=152596360 where 96% of voters said the Gender Recognition Act should be repealed

However, repealing the GRA alone could leave a legal gap. The GRA is not the only source of confusion. Some of the problem comes from older case law too.
There is already case law with the phrase "woman for all practical purposes" in it. This comes from a 2004 House of Lords case involving a transsexual police applicant. The applicant was male, had undergone surgery, and wanted to be treated as female for the purposes of police work. The issue was whether that male could be excluded from the job because police officers sometimes had to carry out same-sex searches. Before the GRA, the court decided that a post-operative transsexual person could be treated as their acquired gender for some practical purposes, including same-sex searches.

That is exactly the kind of ambiguity that needs fixing. Parliament should not simply repeal the GRA and leave older “practical purposes” arguments sitting there as the fallback position.

Whether the GRA is repealed, amended or left in place, we need legislation that clearly and unequivocally states the legal definition of sex, male and female.

The legal definition should say something like:

  • for the purposes of any Act, statutory instrument, public function, policy, data collection, sex-based rule, sex-based exception, sex-based service or sex-based protection, sex means biological sex in human beings, being male or female
  • male means a person whose body developed along the male pathway, organised around the production of small motile gametes, sperm
  • female means a person whose body developed along the female pathway, organised around the production of large immobile gametes, ova
  • man and boy mean male
  • woman and girl mean female
  • sex is observed and recorded at birth, not assigned; a birth record may be corrected where there has been a genuine recording error, but sex is not created by paperwork
  • actual fertility is not required; a person does not stop being male or female because of age, infertility, miscarriage, menopause, hysterectomy, vasectomy, injury, difference or disorder of sex development, medical treatment or surgery
  • people with DSDs are still male or female; DSDs are variations in the development of male or female bodies, not a third sex, and people with DSDs should always be treated with dignity, privacy and respect
  • sex is not determined by chromosomes alone, hormone levels, height, strength, appearance, clothing, hairstyle, voice, breast size, genital appearance, personality, social role, stereotypes, brain claims, feelings, belief or identity
  • sex is not changed by a Gender Recognition Certificate, passport, driving licence, NHS record, deed poll, self-identification, social transition, hormones, puberty blockers, cross-sex hormones, surgery, certificate, document, administrative record, or any other document or procedure
  • non-human examples, such as clownfish or plants, do not alter the legal definition of sex in human beings
  • gender reassignment remains a separate protected characteristic
  • trans people remain protected from discrimination, harassment and victimisation under the Equality Act; this is about defining sex clearly, not removing ordinary legal protections from trans people

This would not stop anyone living as they wish. It would not remove ordinary protections against discrimination, which should always remain. It would simply stop the state and public bodies from treating sex as a paperwork exercise.
Sex is real, binary and immutable. Most of the time, sex does not matter. But in the contexts where it does matter, it matters profoundly: safeguarding, privacy, dignity, data, sport, prisons, healthcare and single-sex services.

A proper legal definition would cut through years of ideological confusion and make the law clear again.

OP posts:
PrettyDamnCosmic · 01/06/2026 16:27

SingleSexSpacesInSchools · 01/06/2026 14:52

This has been a great discussion so far, lot's of points raised I had not considered. Honestly went into it thinking, well of COURSE thats going to be a yes.

Wanted to summarise the positions again a definition in law:

  • We already have a legal meaning of sex, especially after FWS
  • Opening the law up again could be risky, because badly drafted legislation could make things worse.
  • Ordinary people already know what male and female mean, so we should not concede that sex is complicated.
  • The real problem may be paperwork, records and institutions ignoring the law, rather than the lack of a definition.

And the arguments for:

  • FWS clarified the Equality Act, but only that
  • People are still standing up in court saying they are “biologically female” despite being male.
  • A clear definition would stop the endless “it’s complicated” wriggling.
  • Accurate recording of actual sex matters for healthcare, crime data, safeguarding, prisons, sport and population-level decisions.
  • Women should not have to keep litigating the same basic reality over and over again.

I'm not really swung by the arguments against except the one related to drafting a bad law or definition - or far worse possibly - a future government changing the definition to something truly mad and bad for the GC position. That does feel possible. But if things have got that bad, surely the argument would have been lost in public opinion?

Part of my reasoning to have a definition would be to make it easier to criminalise bad actors who enter single sex spaces that don't match their sex. And I think that is going to be needed because I don't think there is going to be widespread compliance with the EHRC code, not to mention the fact that the responsibility is on the service providers, not the users.

We already have a legal definition of sex. It's what is on your original birth certificate. No further definition is required.

SingleSexSpacesInSchools · 01/06/2026 16:33

PrettyDamnCosmic · 01/06/2026 16:27

We already have a legal definition of sex. It's what is on your original birth certificate. No further definition is required.

that's not a definition though.

OP posts:
PrettyDamnCosmic · 01/06/2026 16:44

SingleSexSpacesInSchools · 01/06/2026 16:33

that's not a definition though.

that's not a definition though.

Of course it is. Everybody knows what sex is on their birth certificate. It's following the definition of biological sex in Corbett v. Corbett that it's fixed at birth and determinable by three specific, innate physical criteria: chromosomes, gonads, and genitals. The latter is enough for 99.95% of babies but further investigation of chromosomes may be necessary for the very few where there is a DSD.

MyAmpleSheep · 01/06/2026 16:54

The law isn't there to state facts; we should leave that to encyclopaedias. Neither facts that are true, nor "facts" that aren't. Day is day and night is night regardless of whether there is a law that says "day is night".

Legal definitions operate only within the law. This sounds trite, but it's important. The law cannot legislate to force people to use particular words in certain ways. What it can do is be clear how the words used in laws are to be interpreted.

Like I said earlier, if (even) everyone suddenly agrees to call a cat a dog, that doesn't make the Dangerous Dogs Act suddenly applicable to cats. Cats were not included in the mind of the legislators when the act was passed. They don't get added by dint of a later change of the meaning of a word.

Society can agree that that trans-identifying men are somehow "women", if it wants. (It doesn't want, but that's another issue). Even if that became true it doesn't affect how prior laws are to be read.

FWS didn't really clarify the meaning of men and women at all, because it has never been unclear. What it clarified is which meaning is the one that applies within the EA2010.

And no definition is ever going to stop some men from standing up to say they're women; they will simply say that your new definition is wrong.

SingleSexSpacesInSchools · 01/06/2026 16:55

PrettyDamnCosmic · 01/06/2026 16:44

that's not a definition though.

Of course it is. Everybody knows what sex is on their birth certificate. It's following the definition of biological sex in Corbett v. Corbett that it's fixed at birth and determinable by three specific, innate physical criteria: chromosomes, gonads, and genitals. The latter is enough for 99.95% of babies but further investigation of chromosomes may be necessary for the very few where there is a DSD.

Look I'm not being difficult here but thats definitely NOT a definition. thats not what a definition is. It says male, or female, it does not define those words so it is not a definition.

OP posts:
MyAmpleSheep · 01/06/2026 17:06

PrettyDamnCosmic · 01/06/2026 16:44

that's not a definition though.

Of course it is. Everybody knows what sex is on their birth certificate. It's following the definition of biological sex in Corbett v. Corbett that it's fixed at birth and determinable by three specific, innate physical criteria: chromosomes, gonads, and genitals. The latter is enough for 99.95% of babies but further investigation of chromosomes may be necessary for the very few where there is a DSD.

The latter is enough for 99.95% of babies but further investigation of chromosomes may be necessary for the very few where there is a DSD.

Chromosomes, genitalia and gonadsmay all need further investigation. Corbett doesn't say chromosomes win out.

Corbett leaves the possibility open that someone can be legally male even if they are XX, or female if they are XY in chromosomes. Because in difficult to tell cases the court can make an individual decision, based on medical advice. Until that individual difficult case is brought before a court there is of course no way to tell how a court will rule.

It's also possible that the sex recorded in the register of births (and copied to a birth certificate) is was wrongly recorded, on the Corbett test. There is a recognized procedure for making a marginal note to say so.

The overriding point is that sex has nothing to do with social factors nor an individual's choice, nor is it open to question in the great majority of cases where gonads, genitalia and chromosomes do align.

PrettyDamnCosmic · 01/06/2026 18:00

SingleSexSpacesInSchools · 01/06/2026 16:55

Look I'm not being difficult here but thats definitely NOT a definition. thats not what a definition is. It says male, or female, it does not define those words so it is not a definition.

By definition your legal biological sex is whatever is written on your original birth certificate. How it got to be recorded as M or F is pretty irrelevant but it's a data point that will be correct for 100% of individuals except for a tiny number of individuals with DSDs where the original birth certificate is replaced with a new original birth certificate. It's an infallible definition. Everybody knows what sex is recorded on their original birth certificate even those with a GRC who get issued a replacement birth certificate.

ExitPursuedByABare · 01/06/2026 18:04

I’ve voted no as we shouldn’t bloody need it.

World’s gone mad.

viques · 01/06/2026 18:11

SingleSexSpacesInSchools · 31/05/2026 00:11

I mean I don’t disagree. Clearly. But the fact people keep arguing about it means we clearly DO lack a shared definition?

No, I think the fact that people keep arguing about what defines a woman and what defines a man means

some people don’t know when to stop when the argument is already won

some people don’t understand simple biology

some people have a big agenda in continuing the argument because they think they will eventually wear down the opposition ( its a strategy they probably used as children on tired parents and it might sometimes have worked)

some people have gone so far down the rabbit hole they are scared they will get laughed at if they crawl out now and admit they were wrong.

SingleSexSpacesInSchools · 01/06/2026 18:43

PrettyDamnCosmic · 01/06/2026 18:00

By definition your legal biological sex is whatever is written on your original birth certificate. How it got to be recorded as M or F is pretty irrelevant but it's a data point that will be correct for 100% of individuals except for a tiny number of individuals with DSDs where the original birth certificate is replaced with a new original birth certificate. It's an infallible definition. Everybody knows what sex is recorded on their original birth certificate even those with a GRC who get issued a replacement birth certificate.

What I mean is that it does not define what male or female means. It just says the word and I’m not sure that’s enough

OP posts:
Taztoy · 01/06/2026 18:47

SingleSexSpacesInSchools · 01/06/2026 18:43

What I mean is that it does not define what male or female means. It just says the word and I’m not sure that’s enough

Whatever it’s defined as, it’ll never be enough.

POWNewcastleEastWallsend · Yesterday 03:42

No. It is unnecessary, an irrelevant diversion of time and effort and could be completely counter-productive.

  1. As PP have pointed out, we already have a concise definition based on Case Law.
  2. A tiny minority of people cannot accept reality or refuse to accept reality. Legislation as you propose is not going to change that.
  3. It is also not going to stop a small percentage of straight men involuntarily responding sexually to men with fake breasts as if they are women and perceiving them as a type of female rather than a type of male.
  4. We have already seen what nonsense can be passed into law with the GRA. Get enough "trans allies" in the House of Commons and House of Lords and a draft statutory definition along your lines could end up being amended out of all recognition to say that sex, male and female are "social constructs" or that sex is determined by "brain sex".

We are going to have our work cut out getting people to obey the law in ways that improve things, eg. not by replacing all single-sex toilets with universal toilet rooms or mixed-sex blocks of cubicles.

That is going to be a long slog and not because people need precise definitions of sex, male and female. It is because of politics, economics and ideologically driven attitudes within the "officer class" that are out of step with "the other ranks", ie. the majority.

That said, things are moving in the right direction within Government, even though the Labour Party must be as worried about losing votes to the TWAW Green Party as to TWAM Reform.

LyricalSixties · Yesterday 17:40

No, because I don't think that even more words are needed. The more you try to define 'man' and 'woman', the more space you introduce for those who want to insert a 'but ...' I think the law and rulings on it we have now suffice.

ProudCat · Yesterday 21:00

The thing with language is that words have meanings, actual meanings, and if there's two different words it's because there's two different meanings.

For example:

  • man and boy mean male
  • woman and girl mean female

They don't. Male means male. Female means female. The reason that we have other words is because they mean something different.

Collapsing language for a political purpose is very questionable. And no executive or legislature should get to control the dictionary and create false equivalences because it massively impinges on our freedom of expression - as defined by the Universal Declaration of Human Rights.

And yes, when someone presents something as a simple logic, it never is. Instead, it's always a repressive move, designed to rob people of their critical capacity. When they present it and it looks like it's written by AI, it becomes very clear who (or rather I should say what) is trying to dumb down the discourse into sound bites and for what purpose.

SingleSexSpacesInSchools · Yesterday 23:14

https://www.reddit.com/r/transgenderUK/comments/1tuvk0g/red_state_style_bathroom_bill_for_all_government/

this is still why we need a definition

so this can be illegal

Should the UK have a simple, clear legal definition of sex, male and female?
OP posts:
Zoonosis · Yesterday 23:21

Of course the other solution is you just spend less time stalking trans Reddit, given that there is no piece of legislation you can pass or definition you can insist on that will stop people over there saying things that you disagree with.

SingleSexSpacesInSchools · Yesterday 23:30

Zoonosis · Yesterday 23:21

Of course the other solution is you just spend less time stalking trans Reddit, given that there is no piece of legislation you can pass or definition you can insist on that will stop people over there saying things that you disagree with.

As long as these people remain a danger to my daughter I’ll keep checking up on what they are doing thanks.

and as I mentioned earlier I specifically think it should be criminalised for males to enter female spaces. Clearly TIM will never listen so the cops is the best answer.

OP posts:
HenriettaSwanLeavitt · Yesterday 23:31

SingleSexSpacesInSchools · Yesterday 23:14

Not sure we can legislate against stupidity.

HenriettaSwanLeavitt · Yesterday 23:36

ProudCat · Yesterday 21:00

The thing with language is that words have meanings, actual meanings, and if there's two different words it's because there's two different meanings.

For example:

  • man and boy mean male
  • woman and girl mean female

They don't. Male means male. Female means female. The reason that we have other words is because they mean something different.

Collapsing language for a political purpose is very questionable. And no executive or legislature should get to control the dictionary and create false equivalences because it massively impinges on our freedom of expression - as defined by the Universal Declaration of Human Rights.

And yes, when someone presents something as a simple logic, it never is. Instead, it's always a repressive move, designed to rob people of their critical capacity. When they present it and it looks like it's written by AI, it becomes very clear who (or rather I should say what) is trying to dumb down the discourse into sound bites and for what purpose.

For example:

  • man and boy mean male
  • woman and girl mean female
They don't. Male means male. Female means female.

Man means adult, human male.
Woman means adult, human female.

Male and female are words that are used across species.
Man and woman refer exclusively to the male and female of the human species.

Zoonosis · Yesterday 23:37

SingleSexSpacesInSchools · Yesterday 23:30

As long as these people remain a danger to my daughter I’ll keep checking up on what they are doing thanks.

and as I mentioned earlier I specifically think it should be criminalised for males to enter female spaces. Clearly TIM will never listen so the cops is the best answer.

Edited

Oh stop using your poor daughter as an excuse for your obsessive and hateful behaviour. You're a man who seems to split his time between a forum for mums and stalking total strangers on reddit then getting wound up because you can't control what they think or say. Take a look at yourself.

HenriettaSwanLeavitt · Yesterday 23:41

Zoonosis · Yesterday 23:37

Oh stop using your poor daughter as an excuse for your obsessive and hateful behaviour. You're a man who seems to split his time between a forum for mums and stalking total strangers on reddit then getting wound up because you can't control what they think or say. Take a look at yourself.

Lots of us women here concerned about the children caught up in this shameful ideology too. No harm in looking at reddit; it's an open forum. They come and have a look at mumsnet. In a bizarre way we are communicating, which is good, right?

Zoonosis · Yesterday 23:49

And what "communication" do you think this thread is giving to Reddit except to confirm what they already think - that this board is full of obsessive, controlling, unhinged, bigoted individuals who want to legislate trans people out of existence?

HenriettaSwanLeavitt · Yesterday 23:53

Zoonosis · Yesterday 23:49

And what "communication" do you think this thread is giving to Reddit except to confirm what they already think - that this board is full of obsessive, controlling, unhinged, bigoted individuals who want to legislate trans people out of existence?

You started off so well when you first posted on these threads. You seem to be struggling to maintain your poise.

MyAmpleSheep · Yesterday 23:54

Zoonosis · Yesterday 23:49

And what "communication" do you think this thread is giving to Reddit except to confirm what they already think - that this board is full of obsessive, controlling, unhinged, bigoted individuals who want to legislate trans people out of existence?

I think they might see that people who have differing views to the majority continue to be welcome to post here. As you are proving.

GreyskySexRealistsky · Yesterday 23:55

Zoonosis · Yesterday 23:49

And what "communication" do you think this thread is giving to Reddit except to confirm what they already think - that this board is full of obsessive, controlling, unhinged, bigoted individuals who want to legislate trans people out of existence?

Oooh don't hold back!

Who gives a shit what reddit thinks about this board? They might learn something if they read it
waves 👋

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