The 2017 local elections took place on 4 May 2017, a month before the General Election 2017. Did the results prefigure the outcome of the General Election?

What happened at the 2017 local elections?

The Conservatives won 61% of seats up for election on 4 May 2017 in England, compared with 47% in 2013 when a similar set of seats were contested. Labour won 18% of all seats, down from 23% in 2013. Liberal Democrat share of available seats decreased by 2 percentage points to 13%. UKIP won just one seat, down from 147 seats in 2013 (6%). Our briefing paper Local Elections 2017 provides further information about the results.

Did local elections prefigure the 2017 General Election?

It is difficult to estimate the support political parties get across Great Britain in any given set of local elections because not all local authorities hold elections at the same time. The electoral cycle means that local elections are held in different places and not all councillors are elected at the same time. Because of this, we rely on Rallings and Thrasher’s National Equivalent share of the vote (NEV). NEV uses local election results to estimate how major parties would have performed if elections had taken place throughout Great Britain.

Con NEV estimate: 39%; Con GE2017 share: 43%; Lab NEV: 28%; Lab GE 2017: 41%

Based on the 2017 local election results, in the event of a General Election the Conservatives would have received 39% of the votes in Great Britain and Labour 28% of the votes. However, in reality the Conservatives increased their vote share in Great Britain to 43.3% from 37.7% at the 2015 General Election. Labour’s vote share in Great Britain was 41%, a 9.8 percentage point increase on 2015 and its highest level since 2001.

Liberal Democrat NEV was 18%, 4 percentage points higher than in 2016. The actual Lib Dem vote share in Great Britain was 7.6%, less than half the estimated vote share. Although NEV indicated a decline in UKIP vote share (4%, down from 12% in 2016), its vote share actually declined from 12% in 2015 to 1.8% in 2017.

Has it been accurate before?

Between 1997 and 2015, local elections took place on the same day as general elections and people tended to vote in the same way. In 1983 and 1987, however, there were local elections a month before a General Election. YouGov notes that NEV underestimated the Conservative lead over Labour in both years:  by 13 percentage points in 1983 and by 5 percentage points in 1987. In contrast, in 2017 the estimated Conservative lead over Labour was 9 percentage points higher than the actual gap between the two.

Why the differences?

There are a few explanations for why local election results are not the best indicator of how a possible General Election would play out.  First, turnout at local elections is lower than at general elections. For example, according to Rallings and Thrasher’s local elections handbook, around 34% of the eligible electorate voted in the 2016 local elections. This makes it difficult to anticipate which party potential voters would support.

Second, there are different issues at stake. People might focus on local issues when electing a local councillor without necessarily considering wider party policy. General elections, on the other hand, revolve around political parties’ stance on big issues such as the economy, healthcare and education. Political campaigns are also a powerful tool for engaging with potential voters and influencing how individuals vote in a General Election.

Picture credit: Elections 2010-71 by AdamKR; Creative Commons Attribution-ShareAlike 2.0 Generic (CC BY-SA 2..0)