Response Options and Exiting the EU
By: Anthony B. Masters
Tags: Statistics, Brexit, European Union, Surveys, Polling

A social media post by Conservative MP Steve Baker claimed “the Brexit majority has increased”. Similarly, Brexit Party leader Nigel Farage MEP asserted that Britain is “still Leave”, and “arguably the country is more Leave than it was three years ago”.

Are these claims right? This article examines public survey evidence.

The Binary Question

Steve Baker MP (Conservative, Wycombe) quoted a Mail Online article, under the byline of Prof Matt Goodwin (University of Kent):

Remainers like to claim that, three years on, the facts have changed — that there is actually a voting majority for staying in Europe after all. But the most recent poll suggested that with 57 per cent now backing Leave, the Brexit majority has increased.

When asking if people want to remain or leave the European Union, polling of the EU referendum question and its variants does not show this. The What UK Thinks EU website collates survey data relating to the UK’s relationship with the European Union.

The average Remain share of the last six polls was 52%.

This estimated shift to Remain of four points is principally due to 2016 non-voters preferring Remain to Leave. Whilst almost every poll shows a modest Remain lead, it is not clear that a new referendum would produce a different result to 2016. Such leads can be overturned during the actual campaign.

The Remain average of this rolling average had irregularly increased to 54%, before recently reducing. (Source: What UK Thinks EU)

Where did “57% now back Leave” come from?

This claim comes from a recent YouGov poll for The Times, asking people to rank their preferred outcomes. The internet panel survey of 1,680 GB adults estimated that 43% back “remaining in the EU after all”, whilst 57% were split across three ‘Leave’ options.

The survey was conducted between 17–18th June 2019. (Image: The Times)

The difference between the binary referendum question and this four-option ranking question should be clear: people are being offered different choices.

The choice of options affects survey estimates.

Some people who would back Remain in a binary referendum might prefer a particular Leave option. This four-option ranking question cannot be directly compared to the two-option referendum question in 2016, and is no basis to claim that “the Brexit majority has increased”.

The same questions should be used when comparing opinion over time.

That paragraph was removed from the online article after political scientists highlighted its inaccuracy. Prof Goodwin stated that the inaccurate claim was written by a sub-editor.

British Social Attitudes

Another attitudinal question about the UK’s relationship with the EU has been frequently asked in NatCen’s British Social Attitudes survey. The random probability survey gives five different options (“Do you think Britain’s long-term policy should be…?”):

Full technical details of the British Social Attitudes survey in 2018 may be read here.

In their latest survey reading mainly conducted between July and October 2018, an estimated 34% believed Britain’s long-term policy should be to leave the EU.

This is plainly a lower ‘Leave’ share than contemporaneous surveys which repeat the EU referendum question.

The same principle applies: giving different response options provides different estimates. Additionally, asking people about the country’s “long-term policy” may garner different responses to hypothetical referendums.

Answering the question

The claim that “the Brexit majority has increased” is based on an erroneous comparison. A four-option ranking question should not be compared to a two-option referendum held three years ago.

It is unclear where Nigel Farage MEP’s claims come from. Recent surveys suggest a modest Remain lead in binary questions about the principle of EU membership. This is inconsistent with the suggestion that “the country is more Leave than it was three years ago”.

Britain remains divided over leaving the European Union.