In a world of post-truth politics, we tracked the falsehoods of the election campaign – from the leaders, their parties, and their social media machines

Lies, fake news, “alternative facts”: the world of post-truth politics is a dangerous place. Which is why we at Tortoise have spent this election campaign keeping track of untruths.

We checked politicians’ whoppers against analysis carried out by the independent charity Full Fact and Channel 4 News’s FactCheck, and discovered that of 95 claims that were fact-checked during the election campaign, 77 turned out to be untrue.

But what, in the context of a hard-fought election, actually counts as an “untruth”?

We have used a broad definition to cover statements or manipulations or misrepresentations where politicians strayed from the truth: ranging from the misleading remark to the outright lie.

Over half of the false claims we scrutinised were straightforward errors or exaggerations about facts. One of the smallest was Jeremy Corbyn’s mistaken claim that the UK is the world’s fifth richest country – it’s recently moved down to sixth (or ninth, depending on which measure you use). Not the worst untruth of the campaign, but still an error that a prospective prime minister probably should not make.

Some of these untruths can be classed as “omissions”: claims that miss out important information, such as Siân Berry’s statement during the ITV leaders’ debate that funding for bus services has been cut by nearly half. Full Fact found that this statistic came from a report that, rather significantly, ignores the full picture.

Then there were the conjectures: things that can be neither proven nor disproven, like the SNP saying that Scotland has subsidised the rest of the UK in most of the last 40-year period. Channel 4 found that lack of data makes this impossible to know either way. Again, not a Nixon-level lie: but still a potentially misleading statement.

More troubling were the outright fabrications and deliberate acts of deceit. Phoney images of newspapers on Facebook, or leaflets with flawed evidence to persuade voters to vote tactically. And perhaps worst of all, the fake fact-checker launched on social media as a means of re-badging the Conservative press office Twitter feed during the ITV leaders’ debate on 19 November.

Challenged on the BBC’s Victoria Derbyshire Show with the opinion of one viewer that his son was a liar, like Pinocchio, Johnson’s father Stanley was scornfully dismissive. “Pinocchio? That requires a degree of literacy which I think the Great British public doesn’t necessarily have,” Johnson Sr said. “They couldn’t spell Pinocchio if they tried, I shouldn’t have thought.” We are not so sanguine. If the truth does not matter and lies can be laughed away in the middle of a general election campaign, then what chance does liberal democracy stand?

Who told the most untruths?

Of the 77 untruths we collected, nearly two-thirds came from one of the two main parties, with slightly more from the Tory campaign compared to Labour.

Boris Johnson told the most untruths of the leadership contenders, responsible for nearly half of the Tory’s untruths, compared to Corbyn who accounted for a third of Labour’s.

Which issues were parties the most dishonest about?

Perhaps unsurprisingly, the NHS and Brexit. Labour and the Tories told a total of nine untruths about the NHS. For the Tories, this was most notably the repeated promise of an unprecedented cash boost for our national health service. (After adjusting for inflation, the NHS had a larger cash boost as recently as 2004/05 to 2009/10.)

But what is also striking is that parties tend to be least truthful on the issues closest to their heart: Tories had most untruths about Brexit. Labour had the most about poverty. Almost all of the SNP’s untruths related to the Union.

Where are the untruths coming from?

One of the biggest “platforms” for untruths (and perhaps a sign of how rushed the campaigns have been) was official party literature: manifestos, press releases, leaflets and adverts. A handful of these included crimes against charts, such as Labour’s donut chart, which implied that the 35 per cent of Hornsey and Wood Green constituents who didn’t vote Labour all voted Tory (in fact, the Lib Dems had a higher vote share than the Tories). Joint top was social media, where most of the untruths had no official affiliation to a party.

Who was the most deceitful?

But not all untruths are equal – some are outright lies – and we want to find out who told the worst. To do this, we scored each untruth for the electoral significance of the claim and the level of dishonesty in the lie.

A barrage of untruths

Here you can see all the untruths we looked at, sized by their severity and arranged by time. Tap to discover the truth.