VISITORS TO Sir Keir Starmer’s home in north London report finding a worried man. The Labour leader frets about how he would organise Downing Street, and about the aptitude of some of his staff for government. Above all, he is anxious that he won’t get there at all. His party has wide and consistent leads in opinion polls, leaving many of his colleagues ebullient that they will be taking jobs in government after an election is called next year. Sir Keir himself, however, sees that as hubristic. “People are inhaling the polls. That is a big, big, big mistake,” he said earlier this week.

The results of three parliamentary by-elections in Conservative-held seats on July 20th serve as a political Rorschach test: enough to bolster both Sir Keir’s hopes and his fears. The Tories suffered heavy defeats in two of them: Selby and Ainsty (in North Yorkshire) to Labour, and Somerton and Frome (in Somerset) to the Liberal Democrats. Together these point to a possible landslide defeat for the Conservatives. But, contradicting that narrative, the ruling party narrowly hung on in a third: Uxbridge and South Ruislip in outer west London. According to Rishi Sunak, the prime minister, the Uxbridge result showed how the general election is not a “done deal”. It also looks like a case of pro-environmental policies meeting a backlash at the ballot box.

The three contests were a symptom of Tory malaise after 13 years in office. Boris Johnson, a former prime minister, resigned his seat in Uxbridge on June 9th, after a committee of Parliament concluded he had lied over the Partygate scandal. Nigel Adams, his close ally, stood down as MP for Selby the next day. David Warburton quit in Somerton over allegations of drug-taking, which he admitted, and sexual misconduct, which he denies.

Two seats saw heavy swings, far in excess of that needed in a general election to deliver a change of government. In Selby, Keir Mather (pictured, alongside Sir Keir), aged 25, overturned a Conservative majority of 20,137. The swing of nearly 24 points was the largest Conservative-to-Labour shift since the Dudley West contest of 1994, which preceded a general-election thrashing in 1997. (It was also the second-largest such swing since 1945.) The result reflected voters’ demand for “change” in light of disorder in government and cost-of-living pressures, said Sir Keir. Inflation has started to ease but stood at 7.9% in June.

In Somerton, the Liberal Democrats’ swing of 29 points was their fifth-largest against the Conservatives since 1945, and their fourth by-election victory since the 2019 general election. It suggests the Lib Dems have returned to their historic form as a machine for picking off Tory seats in by-elections. It also suggests the party is also recovering in its historic rural heartlands in south-west England. The Lib Dems have enjoyed a recent surge in wealthier commuter towns near London, too.

The results show the Conservatives caught in a pincer, given a trend towards more (and highly efficient) tactical voting by the anti-Tory electorate. Labour’s vote in Somerton shrank by 10.3 percentage points; the Lib Dems’ vote in Selby fell by 5.3 points “It would seem unwise for Tory MPs to draw any conclusion other than that their party is still in deep electoral trouble,” said Sir John Curtice, a political scientist of the University of Strathclyde.

Yet the party’s success in Uxbridge may encourage it to do just that. Both parties have concluded that Labour’s defeat was due to the Tories’ opposition to the expansion of London’s Ultra Low Emission Zone (ULEZ). It levies a £12.50 ($16) daily charge on cars that don’t meet emissions standards—broadly including diesel vehicles over eight years old or a petrol car over 18 years old. The zone, which currently covers inner London, will be tripled in size to cover the city’s outer boroughs on August 29th. But Uxbridge is heavily car-dependent, and the Tory campaign played on the trope that Sadiq Khan, the Labour mayor of London, and his party are detached from the concerns of the capital’s outer periphery.

The conclusion both parties are drawing is that Labour’s long-established national lead in the opinion polls can be derailed in a short campaign through aggressive campaigning on flashpoint issues of their choosing. The Tories have perfected the trick of behaving like an insurgent opposition despite serving over a decade in government, and in this case successfully turned the contest away from being a referendum on Mr Johnson to one on Mr Khan.

The campaign in Uxbridge is part of a broader Tory strategy on the environment. The government is riding two horses. It embraces decarbonisation and is promising to spend billions of pounds on nuclear power and carbon-capture technology. Yet it also portrays the Labour Party as in hock to a “criminal eco-mob” of green protesters who would jeopardise energy security and have taken to interrupting sports fixtures. The Tory right immediately seized on the result as evidence that climate policies which will increasingly weigh on the individual voter—such as the planned phasing-out of petrol cars and gas boilers—are electorally toxic. Uxbridge-like campaigns may become a fixture.

The Uxbridge result will ultimately bolster Labour’s worried wing, and empower the Tories’ complacent one. It will strengthen the hand of those near to the Labour leader who want to strip the manifesto of any promises that may startle the electorate. (Party figures meet this weekend to flesh out a policy platform.) Already, Labour has slimmed back its plans to spend £28bn per year on decarbonisation, saying the bill is too high. Meanwhile those Tories keen to fight the next election on green issues are at risk of seizing on the result in outer London, and failing to ask searching questions about the party’s dire performances in Selby and Somerton. ■

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