The organisation launched a legal challenge in 2019 over the government’s decision not to include the option of a tick box for the Sikh ethnic group in the proposals for the next census in 2021.

The High Court dismissed the case in December on the grounds that it was ‘premature’ as it should have been made once the census order had been made. The federation has now lodged its case in the Court of Appeal.

While the census questionnaire will include a Sikh response option for religion, the Sikh Federation argues that not everyone who identifies as ethnically Sikh would also identify as Sikh by religion. The group says this would lead to inaccurate numbers of ethnic Sikhs and the group being misrepresented in terms of funding and public service provisions.

Erin Alcock and Rosa Curling of Leigh Day, who represent the Sikh Federation, said: “Our clients consider they have no option but to continue their case to the Court of Appeal. It is crucial that government planning of public services takes Sikhs into account to ensure the particular needs of their community are met. Without a tick box, it is likely this community which faces discrimination already will continue to be excluded from much needed public services.”

An ONS spokesperson said: “We do not comment on ongoing litigation. However, no group will be missed out in the digital-first 2021 census.

“The ONS recommendations follow extensive research and consultation with groups and individuals and everyone who wishes to identify as Sikh will be able to do so. ONS recommends that, as in 2011, the religion question will have a specific Sikh tick box response option and everyone who wishes to identify as Sikh in response to the ethnicity question will be able to do so using the write-in option, supported online by new search-as-you-type functionality.”