Gerard Henderson is known for his sound convictions, his incredible political memory, his tough scrutiny of mainstream media – especially the ABC – and his refusal to give quarter when he believes the record needs correcting. With one of the sharpest media minds in the country, he has spoken with almost everyone who has mattered in Canberra for five decades.

In this important new book on John Malcolm Fraser, Henderson delivers the most interesting account yet of Australia’s fourth-longest-serving prime minister – not just the seven years of his government from November 1975 to March 1983, but also Fraser’s political rise as well as the ideological controversies that followed him long after he lost office. He entered parliament at the very young age of 25 and exited at the still young age of 52.

As a student at Melbourne University from the mid-1960s to the early-1970s, Henderson was ‘very impressed’ with Fraser’s occasional lunchtime talks. In those days, Fraser was widely seen as a conservative, known for his staunch anti-communism, support for the Vietnam War, commitment to the American alliance, and tensions with the more liberal John Gorton, which culminated in Gorton’s downfall as prime minister in 1971.

Henderson treats Fraser as a major political figure – a commanding Liberal leader, a three-time election winner, and a prime minister who restored authority after the chaos of the Whitlam years – while remaining unsentimental about his flaws.

One of the book’s great strengths is Henderson’s forensic scrutiny of Fraser’s memoirs, co-authored with Margaret Simons, particularly Fraser’s recollections of the dismissal. Take Fraser’s late-emerging claim that Sir John Kerr tipped him off by phone on the morning of 11 November 1975 that Whitlam was about to be dismissed. Fraser first made this claim via biographer Philip Ayres in 1987, more than a decade after the event. Kerr, with whom Henderson became acquainted, flatly denied the story and supported his denial with a contemporaneous note written just days after the dismissal.

Fraser’s case rested entirely on memory and a handwritten note that did not surface until the early-2000s and was first published in his memoirs in 2010. Henderson points to multiple anomalies: the handwriting at the top differs markedly from the signature, date and time at the bottom; the signature does not match Fraser’s practice in 1975; and the date appears to have been altered.

Henderson’s claim is precise – that the date, time and signature were added later – yet Fraser and his co-author declined to explain the discrepancies. To accept Fraser’s version over Kerr’s, therefore, requires heavy reliance on Fraser’s memory, which Fraser himself conceded was ‘notoriously fallible’.

Troy Bramston dismisses Henderson’s concerns as ‘rather silly’, leaning on alleged witnesses while omitting contrary testimony from Bob Ellicott QC, soon-to-be attorney-general, who told Henderson the call was too brief for Kerr to have laid down detailed conditions.

Here, the contrast is stark. Henderson anchors his conclusions in documents, timelines and contemporaneous testimony. Bramston asks readers to suspend disbelief – to accept a memory advanced more than a decade after the event, supported by a note of dubious provenance that appeared decades later and contradicts both Kerr’s denial and Ellicott’s recollection.

On Fraser’s post-prime-ministerial years, Henderson argues that his later embrace of causes associated with the left, especially from the late-1990s, marked something of a transformation rather than simple continuity. Fraser, after all, found himself in the 2000s praised by precisely the sort of people who had once reviled him for the dismissal.

I saw this at first hand in 2014 when lunching with Fraser in Melbourne; a passing couple came over to our table to commend his views, cheerfully conceding they had never voted for him, before adding, with some amusement, that on the big issue of the day, offshore refugee processing, they agreed with him rather than his lunch companion.

Here, I respectfully part company with Henderson. I remain unconvinced that Fraser underwent a dramatic ideological U-turn. Rather, he was always what the British once called a wet Tory: shaped by the post-war liberal establishment, paternalistic and interventionist in economics, protectionist on trade, elitist in temperament, and progressive on social policy. These instincts were evident long before Fraser left office.

His record as prime minister bears this out. On SBS, sanctions against apartheid South Africa, the admission of Vietnamese refugees, multiculturalism, engagement with the developing world, family allowances, Aboriginal land rights and tariff protection, Fraser governed consistently as a small-l liberal.

Certainly, in later years, he reversed himself on major questions – the monarchy, the Vietnam War and the American alliance. And in 2010, he resigned from the Liberal party. But as prime minister, he was largely in step with the progressive assumptions of his era. He was a Keynesian, not a Thatcherite: not for Fraser any productivity-enhancing free-market reforms to make the economy more competitive. And to the end, as Henderson acknowledges, he remained a strong defender of Menzies’ legacy. Until his death in 2015, Fraser remained a creature of his political culture.

The British Conservative critique of Edward Heath offers a useful parallel. Like Heath, Britain’s prime minister from 1970 to 1974, Fraser was a custodian rather than a crusader: a pragmatist formed by the post-war settlement and inclined to manage it rather than overturn it. When his party later moved in a sharper, even more ideological direction, Fraser reacted much as Heath did in the Thatcher years – with estrangement and resentment. It was not Fraser who travelled far, but the political ground beneath him that shifted. Still, Henderson’s book deserves high praise. Fair, judicious and often deliciously readable, Malcolm Fraser is essential reading for anyone serious about Australian political history.