A fortnight ago the London School of Economics published a report showing that uniformly the British press had misrepresented and denigrated Jeremy Corbyn from the moment he won the Labour party leadership last year. It was not that he had failed as leader; he was never given a chance to succeed.

LSE researchers found that 75 per cent of articles “either distorted or failed to represent his actual views on subjects”. Worse, in only 11 per cent of stories were his views fairly represented. In terms of tone, less than 10 per cent of reports were judged as positive.

At the time, I suggested that it was difficult to imagine the broadcast media, and especially the BBC, had done any better.

Now the data are in, and – surprise, surprise – the BBC’s performance is even more dismal than that of the press.

The Media Reform Coalition and Birbeck, University of London, studied the coverage in both the press and broadcast media of the recent attempted Labour leadership coup and found “clear and consistent bias” against Corbyn.

Like the LSE report, the new research argues that “imbalanced reporting” has become so grave that it poses a serious threat to the democratic process.

One graph in particular is shocking. It shows how the BBC’s early evening news programme has treated Corbyn – and it ain’t pretty.

The graph shows that the BBC is failing to make even the most minimal efforts at even-handedness. The issues it uses to frame its news coverage are nearly five times more likely to present Corbyn in a negative light. Even worse, BBC news headlines during the study period failed to frame any story in a positive light for Corbyn.

The BBC’s main broadcast rival, ITV, looks positively pro-Corbyn in comparison, even though it was three times more likely to frame its headlines in critical rather than supportive ways.

Amazingly, there are still those who say our assumptions of entrenched and systematic media bias against Corbyn are simply in our imaginations, evidence only that we have been sucked into a Corbyn cult.

But both studies confirm that the only people who have been lured into a cult are those who continue credulously to believe a small neoliberal elite and their spokespeople in the corporate media can give a fair hearing to someone like Corbyn who might threaten their power.

Many have argued that the BBC’s chief political reporter, Laura Kuenssberg, has been acting more like a spokeswoman for Tory Central Office (or for the Parliamentary Labour Party) than a dispassionate journalist. Now we have the definitive proof.