In two days, the UK will vote on whether to remain a part of the European Union, and a key proponent of the Brexit campaign has been former London mayor Boris Johnson. Before he was a politician, Johnson was, for a time, a journalist. And while he was a Brussell’s correspondent, he did more to cement the media stereotype of the bureaucratic bumbling EU than anyone else, as former Times foreign editor Martin Fletcher rehashed over the weekend.

“For 25 years our press has fed the British public a diet of distorted, mendacious and relentlessly hostile stories about the EU — and the journalist who set the tone was Boris Johnson,” Fletcher wrote on Facebook last Friday.

Fletcher writes that he was appointed the Times’ Brussels correspondent in 1999 — 10 years after Boris Johnson started reporting there for The Telegraph. “And I had to live with the consequences.”

Johnson, Fletcher claims, “made his mark in Brussels not through fair and balanced reporting, but through extreme euro-scepticism. He seized every chance to mock or denigrate the EU, filing stories that were undoubtedly colourful but also grotesquely exaggerated or completely untrue.

“The Telegraph loved it. So did the Tory Right.”

Fletcher then references a quote Johnson gave BBC radio in 2005, where the former mayor said:

“Everything I wrote from Brussels, I found was sort of chucking these rocks over the garden wall and I listened to this amazing crash from the greenhouse next door over in England as everything I wrote from Brussels was having this amazing, explosive effect on the Tory party, and it really gave me this I suppose rather weird sense of power.”

Johnson’s reporting had an “explosive” effect on Fleet Street, Fletcher writes:

“They were much more fun than the usual dry and rather complex Brussels fare. News editors on other papers, particularly but not exclusively the tabloids, started pressing their own correspondents to match them. By the time I arrived in Brussels editors only wanted stories about faceless Brussels eurocrats imposing absurd rules on Britain, or scheming Europeans ganging up on us, or British prime ministers fighting plucky rearguard actions against a hostile continent. Much of Fleet Street seemed unable to view the EU through any other prism. It was the only narrative it was interested in.

“Stories that did not bash Brussels, stories that acknowledged the EU’s many achievements, stories that recognised that Britain had many natural allies in Europe and often won important arguments, almost invariably ended up on the spike.”

“Boris Johnson is now campaigning against the cartoon caricature of the EU that he himself created. He is campaigning against a largely fictional EU that bears no relation to reality. That is why he and his fellow Brexiteers could win next week. Johnson may be witty and amusing, just as Donald Rumsfeld was in the run-up to the invasion of Iraq, but he is extremely dangerous. What began as a bit of a jape could inflict terrible damage on this country.”

In the comments to Fletcher’s post, the Times’ Simon de Bruxelles chimed in. “I recall increasingly apoplectic editors demanding to know why we weren’t getting the same stories that Johnson was coming up with week after week. The answer ‘because it isn’t true’ was never considered good enough.”

It’s hardly the first time Johnson’s role in cementing British attitudes towards the EU has been written about by his former colleagues. In February, former Brussels-based Europe correspondent Sarah Helm wrote in The Guardian of that in the 1990s she’d been sent on many a wild goose chase following up dubious stories written by Boris Johnson:

“The myths were usually funny, often absurd, sometimes traceable to a grain of truth, nearly always grossly distorted, or totally untrue. Very often they had first appeared in the Daily Telegraph.

“Usually, their creator was Boris Johnson, who had for some years worked as the Telegraph’s EU correspondent, famous in the press room as a shuffling, shabbily dressed fellow, with a sharp intellect, huge ambition, and a talent for constructing myths.”

And in Andrew Gimson’s 2006 biography of Johnson, he noted how Johnson’s competitors in Brussels were “crippled by an excessive scrupulousness”, which “prevented them from cutting through the monstrous quantities of mostly very dull material with which they were confronted”.

“Meanwhile Boris fell with joy on stories about changes in the rules governing crisps and sausages, which could so easily symbolise the threat posed by Brussels to the British way of life … Boris did not invent euroscepticism, but he became one of its most famous proponents”.

The book quotes the Economist’s correspondent at the time Charles Grant:

“[Johnson’s] supreme point is to entertain so he doesn’t worry too much if his facts are wrong. He’d always put a good joke above the facts. I do remember as Boris became more sceptical, thinking it was an act, because he did it to make his name in the Telegraph.”

Johnson’s journalistic career started at The Times, but he was sacked after fabricating a quote about an archaeological discovery (the quote — attributed to Johnson’s godfather, the historian Colin Lucas — contained incorrect historical information, leading to a complaint). But he landed on his feet, finding a job at The Telegraph, and in 1989 was posted to Brussels, where he stayed for five years.