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There was a time, not long ago, when Britain’s election broadcasting rules largely ensured that candidates got fair access to the limited number of true mass media outlets that shape public opinion.

Britain’s approach has evolved over time. But as the campaign for Thursday’s general election has shown, the media landscape has changed such that mere tweaks may no longer be sufficient. Throughout this campaign, dishonest claims and dirty tactics — spread predominantly online — have rendered the frameworks that once ensured at least a certain degree of fairness during political campaigns largely useless.

In late November, allegations of digital dishonesty mounted minutes after the beginning of the first television debate between British Prime Minister Boris Johnson and Jeremy Corbyn, his Labour Party opponent. Off air, on Twitter, Johnson’s Conservative Party had quietly rebranded its verified campaign headquarters’ news account as “factcheckUK” ahead of the debate.

Amid rampant concerns over fake news and disinformation campaigns, the pro-Conservative Party tweets disguised as posts from a fact-checking group proved a metaphor for this campaign season.

In defense of the rebranding move, Conservative Party member and Foreign Secretary Dominic Raab maintained: “No one gives a toss about social media cut and thrust."

The campaign that followed proved Raab wrong. Tory campaign videos were edited to be deliberately misleading. Reporters were duped into spreading false accusations via Twitter. Perhaps the most startling example emerged this week, after a photo of 4-year-old Jack Williment-Barr, forced to sleep on the floor of a hospital amid a lack of available beds, quickly became a top story in Britain.

To the Conservative Party’s liberal critics, the photo confirmed their concerns over a lack of sufficient funding for Britain’s National Health Service (NHS). But to others, it was an opportunity to stir tensions online. Soon after the photo went viral, posts alleging that it was staged began to gain traction on social media, without any evidence to support that claim. Critics of the Labour Party viewed the claims as evidence that they had become the victims of manipulation.

However, the original story was correct. The owner of a Facebook account that began spreading rumors to the contrary later said she was hacked. Meanwhile, disinformation experts claimed they had noticed other patterns that could point toward a concerted campaign to spread a counternarrative. The existence of such a concerted, large-scale effort has not been proved.

But the rumor’s murky origins nevertheless put a renewed spotlight on concerns over election meddling. Those concerns had also mounted last month, after the conservative government delayed the publication of a report on possible Russian interference in British democratic processes. It is still unclear what the report will say, but both U.S. intelligence services and European institutions have identified disinformation efforts by Russian sources in their elections.

After blasting the British government for delaying the report, however, Corbyn found himself under scrutiny. He presented confidential documents to the press that suggested the NHS might be on the table in upcoming U.S. trade talks — an accusation that could prove damaging to the Tories. But it emerged that the documents, whose authenticity has not been questioned, had surfaced on Reddit. The website said the papers were linked to a campaign that is believed to have originated in Russia.

Despite lingering questions over Russian meddling, this election cycle has shown that Western democracies might not need foreign intelligence services to turn social media into disinformation networks. The result for Britain — and Western democracy on a broader scale — could be dire.

It would not be an exaggeration to say that what’s at stake in this election is the future of Britain: Come Thursday, can Johnson find a majority for his Brexit deal with the European Union? Can the NHS survive in its current form? Will young Britons lose the opportunity to study and work in Europe?

The dirty digital tactics of this campaign, however, have prioritized other questions: Is the photo of a child on the hospital floor real, or is it a fake? Is a fact-check on Brexit really a fact-check, or is it just Conservative Party messaging disguised as journalism?

The never-ending barrage of misleading narratives has appeared to reinforce preconceived perceptions among some and spread distrust among others. Apparently confused by online rumors, one woman took her criticism directly to The Yorkshire Post newspaper — whose sister paper, the Yorkshire Evening Post, was the first to write on the 4-year-old on a hospital floor — to complain about what she believed to be a fake story. In his public response, the Yorkshire Post’s editor, James Mitchinson, made an urgent plea to her and others.

“I urge you to consider which news source you can get in touch with,” Mitchinson wrote, directly addressing the reader. “Who is willing to look you in the eye and tell you they did their best to get it right versus those who pop up on Facebook, spout something so compelling that others share it, and with that undermine the truth and discombobulate decent citizens.”

“Whatever you do, do not believe a stranger on social media who disappears into the night,” Mitchinson added.