The professor will see you now - local elections
In an occasional series, Professor Philip Cowley offers a political science lesson for The House’s readers. Here: local elections
If you tried to design a system to predict how well political parties would do in a forthcoming general election, you would struggle to come up with anything much worse than British local government elections.
Low turnout. Different bits of the country going to the polls at different times, in different ways – thirds, halves, all outs. Varying rates of candidature. And being local elections (the clue is in the name) plenty of local variation.
Yet for all that parochial factors can matter, Conservative councillors did not start losing seats in the mid-90s in droves because they weren’t paying enough attention to potholes; ditto for Lib Dem councillors after 2010 (“Losing Here!”). There is a national message being delivered; it’s just that sometimes it’s difficult to tell exactly what it is.
Ignore the raw numbers – councillors or councils gained and lost – which are as dependent on what happened last time as they are how well a party is doing this time. Focus instead on the estimates of national performance.
There are two of these (one produced by a team at the BBC, the other produced by Colin Rallings and Michael Thrasher) and while they usually differ by a percentage point or two, they are never miles apart. We have these estimates since the early 1980s and they enable sensible year-on-year comparisons.
But remember that these are projections of the local elections, an attempt to estimate what would have happened had there been contests across Britain. They are not forecasts of what will happen at a general election.
Local elections are what Reif and Schmitt termed “second order elections”, used by voters to punish governing parties, and incumbents therefore often do worse.
Despite this, a paper in Electoral Studies showed you could model general election results based on local election shares, if you took into account both mid-term blues and that the Lib Dems often do better in local elections compared to generals. Based on the 2013 and 2014 local elections that model correctly predicted a Conservative victory at the next general election, despite Labour being ahead in those locals.
Local elections are what are known as “second order elections”, used by voters to punish governing parties
Indeed, incumbent governments were behind in the local elections approaching 1992, 2001, 2005, and 2015, and yet still managed re-election. Even a double-digit lead for the Conservatives in 2004 was not sufficient to ensure victory the following year.
Win big in the locals, though, and it can signify something more substantial. In the last 40 years there have only been two occasions when the incumbent government has been turfed out at a general election and replaced by the opposition, in 1997 and 2010. On both occasions, the preceding local elections were a sign of what was to come – with the opposition party leading by at least 15 percentage points.
There is a reason therefore that plenty of pre-election analysis said that Labour needed to be ahead by at least 10 percentage points to be on course for government. The estimates have them just shy of that – nine points on the BBC’s data – but they also have a miserable Conservative performance (the third worst for which we have data) along with a growing vote for the Lib Dems and the Greens.
Decent data may go back 40 years, but that’s still just ten general elections. The geographic detail is always one of the benefits of actual elections and will matter here as much as the overall figures. Nothing in the early analysis of that spatial detail makes last week look any more encouraging for the Conservatives.
Your further reading for this week: C Prosser, Do local elections predict the outcome of the next general election? Forecasting British general elections from local election national vote share estimates, Electoral Studies (2016); K Reif and H Schmitt, Nine second-order national elections – a conceptual framework for the analysis of European election results, European Journal of Political Research (1980)
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