One Nation senator Malcolm Roberts is facing calls to resign after a sustained round of media scrutiny over his podcast commentary and social media activity, in which he called Covid-19 vaccines "killer" "bioweapons," claimed a cabal of asset managers engineered the pandemic, and said it was "highly likely" the US military was conducting chemtrail trials.

The Guardian published its investigation on July 18, 2026, cataloguing Roberts' conspiracy-theory statements across podcasts and public appearances. The material spans more than a decade of the 71-year-old's political career. Roberts was elected to the Senate ten years ago and is the longest-serving One Nation member after party leader Pauline Hanson. A former mining engineer who spent years campaigning against the existence of global warming, Roberts has a well-documented history of conspiracy claims. He has previously backed conspiracy theories about the 9/11 terrorist attacks and the Sandy Hook school shooting (InDaily).

The most recent material includes a June 2026 podcast in which Roberts claimed, without evidence, that Covid vaccines were "killer" "bioweapons" and that the US defence department had a "major say" in their control and development. In a November 2025 podcast, he said the United Nations and the World Economic Forum were destroying democracies by doing the bidding of ultra-wealthy asset managers to create a "new world economic order." In separate podcast appearances, Roberts claimed BlackRock, Vanguard and State Street — three of the world's largest investment firms — control the world's major events behind the scenes and were responsible for starting the Covid pandemic. He also claimed a cabal of ultra-elite figures was behind the global shift toward green energy (The Guardian).

ABC News reported on July 18, 2026 that Roberts falsely claimed half of pregnant women vaccinated against Covid-19 experienced a miscarriage (ABC News). Nine News reported on July 15 that the controversy also referenced a 2012 London mural by graffiti artist Kalen Ockerman, known as Mear One, which contains antisemitic conspiracy-theory imagery (Nine News).

Roberts has also praised US conspiracy theorist Alex Jones, describing him in 2024 as a "beacon of hope," and lauded Russian president Vladimir Putin after the invasion of Ukraine. On the chemtrail claim — the theory that aircraft are secretly spraying chemical or biological agents into the atmosphere — Roberts acknowledged he had no evidence but maintained it was "highly likely" the US military was conducting trials (The Guardian).

Independent MP Allegra Spender called for Roberts to resign. Spender, whose electorate of Wentworth has the highest number of Jewish people in Australia, made the call in response to the mural reference and the broader pattern of conspiracy commentary. Shadow Assistant Minister for Citizenship Dave Sharma described Roberts' comments as "sickening" and "grotesque" (Sky News Australia, via Facebook).

Opposition leader Angus Taylor, who on July 9 warned of an "eternity of pain" if One Nation wins government, turned the pressure onto Hanson. He asked what Hanson intended to do about Roberts and noted she was "in Italy living it up." Hanson has been photographed on a Mediterranean trip with Australia's richest woman, Gina Rinehart, images first published by the AFR. She also met with far-right activist and convicted criminal Tommy Robinson during a "fact-finding" mission to the UK (The Guardian).

Roberts responded on social media on Thursday July 17, 2026, criticising the reports as "selective cherry picking and dishonest distortions by mainstream media to mislead Australians on behalf of their uniparty mates" (The Guardian).

The scrutiny lands as One Nation has surged in polls over the first half of 2026, surpassing the Coalition and briefly Labor, though support appeared to slip slightly in recent weeks. Taylor's "eternity of pain" warning, delivered on July 9, was an early signal that the Coalition recognised the electoral threat. One Nation party members Sean Bell and Tyron Whitten were named alongside Hanson and Roberts in that same Guardian piece (The Guardian, July 9).

The political calculation here is worth pulling apart. Taylor's strategy of targeting Hanson's absence rather than engaging directly with Roberts' claims is a deliberate one. It lets the Coalition pressure One Nation's leadership structure without being seen to litigate the substance of the conspiracy theories themselves. That keeps the focus on Hanson's judgment in managing her own Senate team. But it also leaves the Coalition exposed: if One Nation's polling holds up despite this coverage, the tactic reads as an admission that the Coalition cannot win back voters who have already defected. The crossbench and shadow ministry voices calling for Roberts' resignation, from Spender and Sharma, keep the substantive record on the table. Whether that pressure translates into anything beyond rhetoric depends on whether One Nation's recent dip in the polls is a temporary softening or the start of something more durable. A senator who calls vaccines bioweapons and praises Alex Jones is not a new political problem. He has been saying these things for years. The question is whether the polling surge has made them newly salient — and whether any party in Parliament House has the standing, or the inclination, to act on it.