On Saturday 24 March, demonstrators marched through the streets of Leeds in protest against Brexit. Local police estimated that 2,000 protesters attended.

The BBC covered the demonstration in a small online news piece filed under its regional coverage, and ran the story in a Look North TV bulletin that is unavailable online (ITV News covered it in a regional broadcast that you can read about and watch here).

Former cabinet minister and leading post-referendum Remain campaigner Andrew Adonis tells me it was this moment that “tipped me over the edge”.

Following a number of other editorial decisions by the public broadcaster, including former Ukip leader Nigel Farage’s 32nd appearance on Question Time on 1 March, and the Daily Politics covering the Brexiteers’ publicity stunt flinging fish into the Thames (other news organisations covered it too), the Labour peer has come to the conclusion that “a deep corruption has taken place in the BBC’s news values”.

Tweeting repeatedly about the “#BrexitBroadcastingCorporation”, Adonis has been accusing the BBC of failing to balance its coverage with Remain voices. “The essential debate is between moderate Leavers and Farage and Rees-Mogg,” he says.

“I think this partly is to do with the fact that lots of senior Brexiters effectively took over the organisation in around 2014,” he claims, blaming the decision by Director-General Tony Hall to appoint the former Labour cabinet minister James Purnell as BBC Director of Strategy in 2013. Although Brexit wasn’t a hot debate at that time, Adonis believes right-wingers with eurosceptic views were brought into the BBC to compensate for this appointment.

Although friends with Purnell, Adonis believes this appointment was a “mistaken decision – I don’t think they should have taken on a politician in a very senior role. As a result, they massively over-compensated for having a Labour politician, and a large part of the editorial policy of the BBC seems to have been given over to the Brexiters.”

In listing BBC figures who he feels are sympathetic to Brexit, Adonis names Robbie Gibb, the former editor of the BBC’s Sunday Politics and Daily Politics programmes who went on to be No 10’s communications director, and the presenter Andrew Neil, and claims, “the Today programme’s all part of it too, with John Humphrys and Nick Robinson… It’s deeply infected the whole culture”.

Although BBC figures and Remainers have dismissed Adonis’s theory, Neil has come under increasing scrutiny this week for his associations with Tories and Brexiteers. He is chairman of the Spectator, which backed Leave, and he chairs the Addison Club, a dining and networking group that the Spectator editor Fraser Nelson has called “a Spectator offshoot where a group of people from politics, business and the arts get together”.

Michael Gove has attended, and the Ukip donor and founder of Leave.EU Arron Banks was invited by Neil to speak at the club, according to his book, The Bad Boys of Brexit.

Left-wing commentators like Owen Jones have long been suspicious of Neil being chairman of the Spectator while also working as a top BBC political journalist – finding the former jars with the Corporation’s impartiality – but now all you have to do is search Andrew Neil’s name on Twitter to see floods of Remainers questioning his “agenda” (you can tell they’re anti-Brexit because they have “#FBPE” in their names and tweets – “Follow Back Pro Europe”).

The Guardian and Observer journalist behind the Cambridge Analytica revelations, Carole Cadwalladr, has accused Neil of being “in breach of the BBC’s own code” – citing his online scepticism about her story and tendency to retweet the right-wing Westminster blog Guido Fawkes.

Listen, I don't agree with blanket BBC bashing. But I'm forced to make an exception for @afneil. He's clearly in breach of the BBC's own code. And, apart from that, he's doing his viewers a massive disservice. pic.twitter.com/JXM1moU270 — Carole Cadwalladr (@carolecadwalla) April 3, 2018



And the BBC/Brexit buddy accusations aren’t a new thing among Remainers. Brexit Secretary David Davis’s former adviser-turned-ardent Remainer James Chapman went on a Twitter rant last August accusing his ex-boss of being too chummy with BBC journalists like Neil and Humphrys (they denied his accusations).

The Brexit-sceptic journalist James O’Brien, an LBC presenter who calls Brexit an “almighty con job”, recently wrote in the New Statesman that the British broadcast media has confused the “journalistic principle of impartiality” with “the altogether trickier issue of false equivalence”, arguing that “champions of Brexit” – like climate change sceptics – were booked by producers to make exciting TV and radio, rather than to reflect the reality of the debate.

Anger at the BBC is nowhere near mainstream Remainer opinion, however. Much like their Brexiteer opponents, it’s only the most zealous believers bashing the broadcaster. (For example, when members of the Tory pro-Brexit European Research Group’s demands for “corrections” to broadcast coverage were exposed by BuzzFeed, WhatsApp messages showed the group’s most fervent members were discouraged by more moderate allies.)

Campaigners like Adonis and Alastair Campbell complain to one another about the tone of BBC coverage – but they are the loudest voices, the outliers of a movement that has generally been used to having its views reflected both in the government and on mainstream news channels.

There’s a feeling within the BBC, too, that figures like Adonis, Campbell and Nick Clegg had become accustomed to the BBC chiming with their views after years in power. Hence their anger now they are no longer in the mainstream, and coverage has shifted in an attempt to reflect the current state of the debate.

Adonis suggests this himself, revealing how he now finds it harder to appear on the BBC than Sky News or ITV.

“I was always conventionally pro-Beeb, until I really got into the anti-Brexit thing,” he says. “I was suddenly struck by how systematically pro-Brexit the BBC is… Liberal institutions only work if they serve liberal goals – the point at which they effectively become the handmaiden of extremists, they stop being liberal institutions.”

The pressure in BBC newsrooms to avoid accusations of bias is at its greatest since the EU referendum, due to Remainers recently joining Brexiteers in attacking the BBC’s coverage. Voices on both sides are becoming ever more passionate as the departure date nears, which makes BBC journalists’ jobs increasingly difficult as they are attacked from all sides – rather than merely the usual grumblings in the right-wing press.

“In recent years, we have seen in our survey data and in other research that there is an increasing number of people on the left who are also discontent with the BBC,” says Rasmus Kleis Nielsen, director of research at the Reuters Institute for the Study of Journalism. “Particularly around Brexit but also around its coverage of Jeremy Corbyn as leader of the Labour party.”

Undermining trust in the BBC could lead to partisan broadcast media, warns the BBC’s Today presenter and former political editor Nick Robinson in this week’s New Statesman. “We know where this sort of journalism would lead us if it spread beyond radio talk shows and phone-ins. You would end up with Fox News or a British equivalent,” he warns. “Rupert Murdoch dreams of tearing up the law on broadcast impartiality here, just as it was torn up in America in the Reagan era.”

But there is frustration among BBC staff at politically-charged tweets by big beasts like Neil and world affairs editor John Simpson (who has tweeted: “MP wants details of anti-Brexit university teachers. Decent folks deported on technicalities. Daily hate in press. Doesn’t feel like my country now”), who point out that they would be disciplined for publicly wading into the Brexit debate with their own opinions.

The key thing the Remainers’ anti-BBC turn reveals is a divide within the pro-European camp. Adonis feels some of his allies against a hard Brexit aren’t up for the fight. He divides the Remain contingent into two groups:

“The Snowflake Tendency, who think it’s all over and we should roll over – and the Resistance Tendency. I’ve essentially become leader of the resistance without quite realising,” he says, telling me that he sees his fellow Labour politician, the shadow Brexit secretary Keir Starmer, as “the leader of the Game Over Brigade”.

“[It’s] one of the big debates taking place in Remain,” he says. “And the BBC thing in the past week has defined it, because I’ve been flooded by snowflakes telling me I shouldn’t be attacking the BBC because it's a great liberal institution.”

A BBC spokesperson comments: