23rd June 2024

Eight years ago today, the nation voted to leave the European Union by the now notorious margin of 52% to 48%. By the time we began tracking attitudes towards Brexit in mid-2018, public opinion had already flipped, with just over half of those expressing a preference in favour of re-joining the EU, and just under half opposed. That trend remained steady for two and a half years, until things began to shift in early 2021.

What happened in early 2021 to change public opinion? Well, Brexit happened. On the last day of 2020, the Brexit transition period ended and the UK formally separated from the EU. This marked the moment when the UK ceased to be subject to EU laws and left the Single Market and Customs Union. In the months that followed, as the effects of Brexit began to bite, the steady trend in our tracker was disrupted. Gradually, the number of people reporting that they would vote to re-join the EU if a second referendum were held started to tick up. This was driven largely by a decline in the numbers telling us they were undecided about how they would vote, with little change in the level of support for staying out of the EU. Now, eight years on from the original referendum and three and a half years out from formal separation, a clear majority of those who express a preference in our polls would vote to re-join if a second referendum were held.

So what explains the shift towards pro-EU sentiment in the electorate?

One factor is that many voters have changed their minds. If a week is a long time in politics, eight years is a very long time. At the aggregate level, voters of all ages have become more likely to support membership of the EU since Brexit, and the change is especially pronounced among younger voters. This change is depicted on the graph below by the gap between the yellow line, showing current opposition to Brexit, and the blue line, which shows opposition in the 2016 referendum.

The other half of the story is demographic change. Since the referendum was held in 2016, a significant cohort of voters who did not have a say in that vote have come of age. As the graph shows, opposition to Brexit is highest among younger voters. In particular, those aged between 18 and 25 overwhelmingly oppose Brexit, but their opinion was not counted in the original referendum. This group now comprises around 10% of the electorate – possibly enough to swing the result of a second referendum all on their own. At the other end of the spectrum, older voters were most likely to vote Leave, and just as younger voters have graduated into the electorate, a significant proportion of these older voters have – so to speak – graduated out.

Together, changed demographics and changed minds have produced a markedly different state of public opinion towards the EU than prevailed in 2016. Given this sea change in public opinion, it is curious that relations with the EU have not figured more prominently in the election campaign so far. The Liberal Democrat manifesto includes a pledge to re-enter the Single Market, but this policy has not been at the centre of their campaign strategy. Likewise, Labour has pledged to strengthen ties with the EU, but the precise form of this proposed new relationship remains unclear.

Although there appears to be little appetite for relitigating Brexit among the major political parties at the moment, that may change if the balance of public opinion continues to shift towards re-joining the EU. If that happens, it is only a matter of time before one of the parties sees political benefit in putting Brexit back up for debate.

Matthew PriceAuthor: Matthew Price