Local election results were due to Conservative failure rather than Labour success

Maybe that will prove enough to deliver the party a victory when the next general election comes – but perhaps it would not be wise for them to rely on it, writes John Curtice

Labour spokespersons were keen to argue that the results demonstrated Sir Keir Starmer’s success (PA)

Labour’s response to Thursday’s local election results was simple. As soon as the party registered its first advances in the relatively limited number of councils that had opted to count the ballots overnight, its spokespersons were claiming the results showed the party was “on course” to win an overall majority at the next general election.

And those claims were not without foundation. When aggregated up to current parliamentary constituencies (something that has, however, become increasingly difficult because of ward boundary changes), the party can be found to be ahead in many a seat won by the Conservatives in 2019.

For example, according to the detailed results collected by the BBC, Labour were ahead in Calder Valley, Colne Valley, Dewsbury, Ipswich, and Plymouth Moor View – all of them places where all three main parties fought all the component wards. On average the swing from Conservative to Labour since the last general election in these key marginals was 12 per cent – precisely the swing that on the current constituency boundaries Labour might well need to secure an overall majority of one.

However, people do not necessarily vote in local elections in the way they would in a general election. In particular, they are more inclined to vote Liberal Democrat in local elections while, as Thursday’s results underlined, the Greens are also beginning to put down roots in English local government. So, we cannot simply add up Thursday’s results and use the resulting numbers as a yardstick with which to measure Labour’s progress.

What we can do is to examine whether the progress Labour made in the local elections matches what we might expect given the change in party fortunes in the opinion polls. The current average lead of 16 points over the Conservatives represents a five-point swing from Conservative to Labour since May 2019; that is, when most of the seats being contested on Thursday were last up for grabs. The average swing since 2019 in wards where the BBC collected the detailed voting figures was, however, closer to 4 per cent.

The swing in the polls since this time last year is also five points. However, according to the BBC’s figures, the swing since then in the local elections was only 2 per cent. In short, it is not clear that the swing to Labour in the local elections was fully in line with what might have been expected given the party’s current lead in the opinion polls – albeit that Labour put in a stronger performance than in any previous round of local elections since 2010.

Meanwhile, we should remember that gaining seats – Labour added over 500 to its existing tally – does not necessarily mean that a party has enhanced its standing among the public. Seats won and lost under the first past the post system are a reflection of changes in the relative performance of the parties, not in their absolute share of the vote. A party will gain seats if it simply maintains its own share of the vote while that of its opponents falls.

That is very much the story of Labour’s performance on Thursday. The party was winning more votes than the Conservatives in many a parliamentary seat not because Labour’s own share of the vote was higher than in December 2019, but because support for the Conservatives was now sharply lower.

On average across 27 constituencies where it is possible to use the BBC’s data to compare the parties’ performances in the local elections with that in the 2019 general election, the Conservative share of the vote was down 19 points while Labour’s own tally was unchanged.

Much the same picture emerges if we unpack the swing from Conservative to Labour since last year’s local elections. Conservative support was down by four points, while Labour’s was little changed.

As well as claiming that the local election results showed that Labour was on course to win an overall parliamentary majority, Labour spokespersons were also keen to argue that they demonstrated that Sir Keir Starmer’s success in changing his party has transformed its electoral prospects. In truth, the local election results raise questions about that claim too. What is much more apparent is the scale of the public’s disenchantment with the Conservatives.

Maybe that will prove enough to deliver Labour victory when the next general election comes – but perhaps it would not be wise for the party to rely on it.

John Curtice is professor of politics at Strathclyde University, and senior research fellow at both National Centre for Social Research and The UK in a Changing Europe