“If they will stop telling lies about us,” Harold Wilson once said of the Conservatives, “we will stop telling the truth about them.”  It was a good quip, albeit one that the then Labour Prime Minister had plagiarised from American politics.

In what seems like every general election campaign since Wilson’s time, the Labour Party has claimed that the NHS would not be safe in Conservative hands. This was the expression of an opinion, a fear, rather than a falsehood. “Safe,” after all, is a relative concept.  Selling off is not. Jeremy Corbyn’s assertion that “we’ve got evidence that under Boris Johnson the NHS is on the table and will be up for sale” is an election stunt as authentic as the Zinoviev Letter.

Labour could have confined its attack to the potential of higher drug charges if a future US-UK trade deal grants improved patent terms to the Americans. The reality that the leaked documents of early stage UK-US discussions (not even formal negotiations) showed no such commitment may be brushed aside. It is not illegitimate for Labour to request clarity, highlight the danger and pose as the guardians of the national interest on the subject. 

Only by an Olympian long-jump is it possible to leap from the American drug patent question to the spectre that Labour creates when it invites the public to “imagine opening a five-figure bill for your cancer treatment. Imagine paying to give birth. Paying to have a check-up at the GP. That’s what Boris Johnson and Donald Trump want.”  Imagine, indeed.

The misinformation goes further. Labour has launched a viral social media campaign stating that the cost of the welfare state is trivial.  A Briton on the princely salary of £82,000 pays “£9 per month for Spotify, £10 for Netflix and £8.33 per month in your subscription to: free healthcare, free education, properly funding the NHS …” etc. etc.  Click the link, tap-in your salary, and you will then be reassured that you’ll see no income tax or national insurance rises so “don’t be fooled by the fake news Tories.” This is a bit rich given the misleading phrasing of Labour’s £8.33 a month claim – confusing an increase in the cost with the total bill.

Jeremy Corbyn’s ‘evidence’ that the NHS will be up for sale is about as authentic as the Zinoviev Letter

Why has it taken until this election for Labour to rely so heavily on such audacious misrepresentations?  When you are fighting against a Tory party that many Corbynistas believe embodies racism, homophobia, misogyny, Islamophobia, environmental catastrophe, hatred of the poor, hatred of the weak, hatred of single mothers and working women and all foreigners except Donald Trump, it may seem legitimate for ends to justify means. The Tories must be defeated, by any means necessary.

But there is another possibility. Labour feels it is untouchable over the allegations it makes because it is Boris Johnson who has to rebut each claim. 

The perception that Boris Johnson is a stranger to truth, an incontinent liar in both private and public life, helps Labour to get away with its own misinformation.  As the Labour Party chairman, Ian Lavery, paints Johnson, “he cannot seem to open his mouth without telling a lie. You cannot trust a word he says.”

This is character assassination at its most potent: if Johnson denies something, then – given the manner of the man – it must be true. And getting him to deny an allegation gives greater publicity to the claim in the first place. 

Even Johnson loyalists should concede that this is a rod the Prime Minister has made for his own back. Given his litany of misleading statements and downright untruths, he suffers a trust deficit that he cannot shake off. A politician who is widely assumed to be a liar will always have difficulty defending himself against serious charges, even when they are themselves vehicles of deceit.  Any competent criminal barrister knows that one of the best defences for their client is to cast doubt in the jury’s mind about the reliability and trustworthiness of the accuser. 

During the Brexit referendum, Vote Leave’s decision to feature on the side of its red bus a figure for UK contributions to Brussels that did not factor-in the rebate has done more than give Remainers ammunition for maintaining the electorate was manipulated. As inflated claims go, it was hardly the only exaggeration of that referendum campaign – a temptation to stretch facts and project expectations as if they were established facts which Remainers also succumbed with ready abandon – and do so still.  

But it was the words on the red bus that proved to be the most notorious example and, as such, it has allowed Labour (and the Lib Dems and SNP) to constantly reference it as a means of undermining Johnson’s integrity. What a godsend it has proved. And with what unconstrained abandon Labour wields this gift.