The consultation draft COP for Services, public functions and associations says:
Gender reassignment
11.35 The prohibition on gender reassignment discrimination does not apply in relation to the provision of separate- and single-sex services, provided that the treatment is a proportionate means of achieving a legitimate aim.
and:
Gender reassignment discrimination and separate and single-sex services
15.52 A service provider will not breach the prohibition on gender reassignment discrimination in relation to the provision of separate (including where these are different) or single-sex services, but only if such provision is a proportionate means of achieving a legitimate aim.
The service provider will be expected to consider the needs and wishes of the transsexual person as well as those of the women or men using separate or single-sex services.
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The final COP for Services, public functions and associations says:
Gender reassignment discrimination and separate and single-sex services
13.57 If a service provider provides single- or separate sex services for women and men, or provides services differently to women and men, they should treat transsexual people according to the gender role in which they present. However, the Act does permit the service provider to provide a different service or exclude a person from the service who is proposing to undergo, is undergoing or who has undergone gender reassignment. This will only be lawful where the exclusion is a proportionate means of achieving a legitimate. [sic]
13.58 The intention is to ensure that the transsexual person is treated in a way that best meets their needs. Service providers need to be aware that transsexual people may need access to services relating to their birth sex which are otherwise provided only to people of that sex. For example, a transsexual man may need access to breast screening or gynaecological services. In order to protect the privacy of all users, it is recommended that the service provider should discuss with any transsexual service users the best way to enable them to have access to the service.
Example:
A clothes shop has separate changing areas for male and female customers to try on garments in cubicles. The shop concludes that it would not be appropriate or necessary to exclude a transsexual woman from the female changing room as privacy and decency of all users can be assured by the provision of separate cubicles.
13.59 Service providers should be aware that where a transsexual person is visually and for all practical purposes indistinguishable from a non-transsexual person of that gender, they should normally be treated according to their acquired gender, unless there are strong reasons to the contrary.
13.60 As stated at the beginning of this chapter, any exception to the prohibition of discrimination must be applied as restrictively as possible and the denial of a service to a transsexual person should only occur in exceptional circumstances. A service provider can have a policy on provision of the service to transsexual users but should apply this policy on a case-by-case basis in order to determine whether the exclusion of a transsexual person is proportionate in the individual circumstances. Service providers will need to balance the need of the transsexual person for the service and the detriment to them if they are denied access, against the needs of other service users and any detriment that may affect them if the transsexual person has access to the service. To do this will often require discussion with service users (maintaining confidentiality for the transsexual service user). Care should be taken in each case to avoid a decision based on ignorance or prejudice. Also, the provider will need to show that a less discriminatory way to achieve the objective was not available.
www.equalityhumanrights.com/en/publication-download/services-public-functions-and-associations-statutory-code-practice