EHRC Equality Act (2010) protected characteristic definition

In the Equality Act, sex can mean either male or female, or a group of people like men or boys, or women or girls.

EHRC statement on sex and gender reassignment: legal protections and language (2018, and current as per checked with EHRC Scotland, 27 Oct 2021):
'Gender’ refers to socially constructed roles of women and men and/or an individual’s conception of their identity. The term is often used interchangeably with ‘sex’, partly in recognition that much of the inequality between women and men is driven by underlying social and power structures rather than by biological sex. Although the Equality Act protects people from discrimination because of their sex, other UK legislation (such as the regulations requiring employers to publish their gender pay gap) refers to gender. This may cause confusion in some circumstances. To avoid any ambiguity, we are reviewing our use of language across our website and publications to ensure clarity and consistency. However, it is important to note that any mistaken or structural use of the term gender does not affect how the law works in practice.

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