Do Politicians Keep Their Campaign Promises?

That’s politics for you: Ahead of an election political parties and politicians make outlandish promises often, I suspect, with very little thought whether their plans ultimately can be implemented or not. Examples are the recent election of Zohran Mamdani as mayor of New York and his pledge of city run grocery stores and free buses or the British Labour Party’s promise not to increases taxes.

Mr Mamdani will struggle to find the funding to pay for his plans, as tax increases fall under the authority of Kathy Hochul, the governor of the state of New York. Similarly a huge hole in her budget will most likely compel Rachel Reeves, the British Chancellor of the Exchequer, to increase taxes by more than just the odd tweak here or there when she announces her budget on 26 November.

Labour pledged not to increase the tax burden on working people in its manifesto, this would not be worth thinking about were it not for the Treasury’s definition of ‚working people‘. According to their internal definition as obtained by Sky News this includes only persons earning £45‘000 a year or less. So if you happen to earn more, the promise made last year doesn’t apply anyway – and you should steel yourself for some nasty surprises coming your way. Having said that, the budget shortfall is so deep, and the Chancellor already said as much in recent days, that everyone will have to do their bit.

Conventional wisdom has it that politicians are bad at keeping their campaign promises, but surprisingly their record is better than expected. Large comparative studies find that parties that enter government tend to fulfill a large share of their pledges, while parties that remain in opposition fulfil far fewer. The influential comparative study by Thomson et al analyzed tens of thousands of pledges across many countries and reports generally high fulfillment for governing parties (with substantial variation).

Some governments (especially single-party majority executives) have very high fulfillment on many pledges; some coalition or minority governments fulfill fewer, and some parties or specific pledges (e.g., big structural reforms) are much harder to deliver. Pledge type matters: status-quo or small administrative pledges are far likelier to be completed than large redistributive reforms.

A major comparative study of 18,743 pledges across 12 democracies in 2017 found that governing parties typically fulfil a large share of pledges; fulfilment is much higher for parties that actually enter government vs. those that remain in opposition, and single-party executives show the highest fulfilment rates.

Parties tend to promise things they believe they can deliver within normal institutional and budget constraints. Pledge content often focuses on incremental policy adjustments (funding changes, administrative reforms, minor tax tweaks) rather than radical system overhauls. Large-scale or transformative promises exist, but they make up a small share of total manifesto commitments.

Not so with politicians it seems, as their record of keeping their promises is exceedingly bad. While parties are keeping 60-90% of their pledges, heads of government and presidents do so at a rate of 40-60%. Individual legislators or candidates however live up to only 30-50% of their promises.

Some even do worse than the average (although this may in part be due to structural limits rather than deliberate deceit): According to PolitiFact, a fact-checking website, President Trump during his first term kept approximately 24% of his promises, compromised on 23% and broke or stalled on 53%. And he doesn’t do any better during his current term (you can check his scorecard here). Former French President Francois Hollande campaigned on 60 “engagements” for social-democratic reform, but, according to independent French watchdogs (e.g., Le Monde’s pledge tracker) got roughly one-third fully implemented, one-third partial and one-third unfulfilled.

It turns out that politicians, those perennial scapegoats of public disappointment, are rather better at keeping their word than the public gives them credit for. Across advanced democracies, most governing parties fulfil a solid majority of their pledges. It is, admittedly, a dispiriting finding for those who prefer their cynicism data-driven.

The explanation is less moral reformation than managerial realism. Manifestos have evolved from visionary treatises into carefully costed to-do lists, vetted by civil servants, accountants and, one suspects, the occasional risk analyst. The modern politician’s promise is less a leap of faith than a legally binding project plan. When they break one, it is usually because the Treasury, the courts or geopolitical reality have inconveniently refused to cooperate.

Still, the myth of the “broken promise” persists, perhaps because voters remember the showy failures—walls that remain theoretical, taxes that rise despite solemn vows—more than the humdrum successes of incremental policy. No one ever won re-election by boasting that they modestly restructured a regional grant formula exactly as promised.

If anything, the real scandal may be that promises have become so cautious that keeping them is no longer impressive. A generation ago, a campaign might pledge to reinvent society; today’s equivalent commits to piloting a new online portal. The age of ideological daring has given way to the era of administratively achievable goals.

Voters, of course, will continue to suspect the worst. But perhaps the greatest political deception of all is not that politicians break their promises—it’s that they’ve learned to make only the sort they can safely keep.

As for Britain, we‘ll find out on Wednesday whether the Labour Party‘s pledge not to raise taxes is going to be broken.