Peter Oborne is a consummate receipt-keeper. His efforts to hold political elites to account go well beyond those of regular reporting, and have snowballed over the last 20 years into a one-man moral crusade against lying in public life. He tackled the issue head-on in his 2005 book The Rise of Political Lying, the same year that he presented a Channel 4 documentary Why Politicians Can't Tell the Truth. He reveals in his new book that "by the time the Blair premiership ended in 2007, I had got into the habit of keeping a file of political lies". The figure who has come to dominate that file during the past five years is our current prime minister.

The Assault on Truth may sound like another book about "post-truth", "fake news" or the threat posed by French philosophers. But make no mistake: this is a book about Boris Johnson. Oborne is clinical and merciless in his account of Johnson's mendacity, building up his case item by item, footnote by footnote. The forensic nature of the task leads him to adopt an entire new citation system, such that the bottom third of a page is often made up of URLs, dates and textual references. The book it most reminded me of was Christopher Hitchens's The Trial of Henry Kissinger. In a sane world it would be a political obituary.

[...] It is a relief, in many ways, that social media features so little in a book on political lies. There is something determinedly analogue about Oborne's mission, and the faith he places in official documentation such as Hansard. And yet it becomes hard to explain the rise of Johnson's (or Trump's) brand of free-wheeling political entertainment without at some point addressing changes in the technologies and funding of our media. Johnson's lies are no secret, though they have rarely been as well documented as they are in The Assault on Truth. The question is why they – and books such as this – do him so little harm. In a world of peer-to-peer surveillance, where our honesty and character are constantly being tracked by managers, credit-raters, customers and one another, there is a certain relief in the spectacle of the outrageous leader who seems immune to this collection of "receipts". In the meantime, Oborne offers a stirring rage against the dying of the establishment light.