Happy World Statistics Day – Sex in the Census

Below is the text of a letter we have sent today to Ian Diamond, National Statistician, Head of the Government Statistical Service (GSS) and Chief Executive of the UK Statistics Authority.

Dear Sir Ian,

Today is World Statistics Day and we are writing to you on behalf of many women across the UK who are concerned about the loss of robust, high quality data on sex.

On Sunday evening, Woman’s Place UK hosted its 31st public event since September 2017, and its 4th webinar since the Covid pandemic made it impossible for us to hold meetings in person.

The topic of the webinar was ‘Sex in the census’ and we hosted three speakers who each spoke about the way in which the UK census authorities have approached the development of questions on sex and gender identity for the next UK census.

We received unprecedented levels of interest in this event, with just under 1,000 people registering a place. In the end, almost 500 people logged in on a Sunday evening to hear and take part in a discussion about the importance of sex-disaggregated data and the census.

When Woman’s Place UK formed three years ago, we had five aims. The most pressing of these was to enable women to participate in the debate about reform of the Gender Recognition Act. Another aim was to ensure that the Government “consult on how self-declaration will impact upon data gathering – such as crime, employment, pay and health statistics – and monitoring of sex-based discrimination such as the gender pay gap”.

Indeed, one of our first acts as a newly formed campaign group was to launch a petition to ensure that ONS retained the sex question in the 2021 census.

We have always viewed the collection of sex-disaggregated data as a vital tool in both measuring and remedying the discrimination experienced by women on the basis of sex. When we updated our aims in early 2019, we retained the one on data (“Rigorous collection and analysis of sex-based data and high-quality research must be central to the development of any services, policies or action which address women’s needs or which challenge sex discrimination and inequality”).

For some time now, we have been concerned about changes to data collection exercises which have either conflated ‘sex’ and ‘gender identity’ (two distinct, separate demographic variables) or ceased collecting data on sex entirely.

Over the last two years, we have submitted evidence to the Scottish Parliament, the UK Parliament’s Public Accounts Committee and the Office for Statistics Regulation.

We are pleased that ONS decided to preserve a mandatory, binary sex question for the 2021 census. However, we are extremely concerned that guidance proposed to accompany the sex question effectively makes it a question about self-declared gender identity, not biological sex.

As we learned from Sunday’s webinar, the UK census authorities have arrived at this place by privileging the views and demands of groups claiming to represent the trans community over and above the interests of women, but also those of expert data users.

It is our understanding that the guidance for the 2021 census will soon be finalised. We call on you to address the concerns expressed by the UK’s leading social scientists in their letter to you sent in December 2019, but also the concerns of all the women who attended our event, whose consternation at this proposal was palpable.

We look forward to hearing from you.


20th October 2020


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