He says that removing a male transgender person with a penis from a women's ward because some of the women feel uncomfortable (perhaps because they fear being raped, perhaps just discomfort at being placed in such a situation with a male while they are vulnerable) is not a 'legitimate aim'.
He is wrong. And I quote from Schedule 3, Part 7 of the Equality Act 2010:
Single-sex services
27(1)A person does not contravene section 29, so far as relating to sex discrimination, by providing a service only to persons of one sex if—
(a)any of the conditions in sub-paragraphs (2) to (7) is satisfied, and
(b)the limited provision is a proportionate means of achieving a legitimate aim.
(2)The condition is that only persons of that sex have need of the service.
(3)The condition is that—
(a)the service is also provided jointly for persons of both sexes, and
(b)the service would be insufficiently effective were it only to be provided jointly.
(4)The condition is that—
(a)a joint service for persons of both sexes would be less effective, and
(b)the extent to which the service is required by persons of each sex makes it not reasonably practicable to provide separate services.
(5)The condition is that the service is provided at a place which is, or is part of—
(a)a hospital, or
(b)another establishment for persons requiring special care, supervision or attention.
(6)The condition is that—
(a)the service is provided for, or is likely to be used by, two or more persons at the same time, and
(b)the circumstances are such that a person of one sex might reasonably object to the presence of a person of the opposite sex.
(7)The condition is that—
(a)there is likely to be physical contact between a person (A) to whom the service is provided and another person (B), and
(b)B might reasonably object if A were not of the same sex as B.
Note that conditions 6 and 7 specifically refer to it being reasonable to object to the presence of another person purely because they are of the opposite sex. This includes women's feelings of discomfort at having their privacy and dignity violated by the presence of men.
Note also that no reasonableness test is required in the case of hospitals. The fact that it is a hospital is enough reason to separate the sexes. Furthermore, the Equality Act 2010 goes on to specifically refer to
Gender reassignment
28(1)A person does not contravene section 29, so far as relating to gender reassignment discrimination, only because of anything done in relation to a matter within sub-paragraph (2) if the conduct in question is a proportionate means of achieving a legitimate aim.
(2)The matters are—
(a)the provision of separate services for persons of each sex;
(b)the provision of separate services differently for persons of each sex;
(c)the provision of a service only to persons of one sex.
As the judgement in For Women Scotland vs Scottish Government reminds us, for the purposes of the Equality Act 2010, there are men with the protected characteristic of gender reassignment and women with the protected characteristic of gender reassignment, with men defined as males of any age and women defined as females of any age.
And that provisions made only for women by definition exclude biological males.
Although this judgement is not binding on courts in England and Wales, it is the most recent interpretation of the Equality Act in this regard, made by the highest civil court in Scotland, and it does therefore carry considerable weight when deciding on these matters.
So, Lord Fetherington is wrong and he makes the usual mistake of forgetting that the discrimination provisions are mainly about not excluding a man with the protected characteristic of gender reassignment from services and spaces provided for all other men and not excluding a woman with the protected characteristic of gender reassignment from services and spaces provided for all other women. As well as not treating those with the protected characteristic of gender reassignment less favourably than members of their own sex in all other areas of public life.
Stonewall et al have advised public and private sector organisations for years now that it's all about not excluding those with the protected characteristic of gender reassignment from services and spaces provided for the opposite sex, and that has skewed the understanding of this to our detriment. But they did not tell the whole story, did they?