# Paul D. Thacker

Paul D. Thacker is an American journalist and anti-vaccine activist who reports on science, medicine, and the environment, but has been accused of anti-vaccine activism and promoting Big Pharma conspiracy theories. He was a lead investigator of the United States Senate Committee on Finance for Senator Chuck Grassley, where he examined financial links between physicians and pharmaceutical companies.

## Early life

Thacker was raised in California and Texas, and joined the US Army after high school, where he was deployed in Saudi Arabia and Iraq during the Gulf War. He earned a Bachelor of Science degree in biology, with an emphasis in ecology and evolution, from the University of California, Davis in 1997. He worked as a laboratory technician at Emory University before turning to journalism, leaving Emory for an Audubon magazine internship in 2000.

## Career

After 2000, Thacker wrote for publications such as The New Republic and Salon and was a staff writer with Environmental Science & Technology, a journal of the American Chemical Society (ACS). Here he published a series of exposés that a senior ACS official claimed showed an anti-industry bias, culminating in an article on the Weinberg Group that resulted in him being fired by the journal in 2006. In Thacker's Weinberg Group story he wrote about a letter that group sent to DuPont outlining a plan to protect DuPont from litigation and regulation over Teflon. The Weinberg Group had done similar work for Big Tobacco and then began working in Europe to defeat alcohol regulations. ACS editor Rudy Baum called the Weinberg article a "hatchet job". In 2006, the Weinberg article won a second place prize in annual awards presented by the US Society of Environmental Journalists. Later that year, Thacker's work was profiled on Exposé: America's Investigative Reports.
In 2007, Thacker joined the United States Senate Committee on Finance for Republican Senator Chuck Grassley, investigating medical research conflicts of interest. Among his work he identified several physicians who had failed to disclose payments from drug and medical companies, including psychiatrist Charles Nemeroff. He also led the committee's investigation of the drug Avandia, which included a report that a medical journal had published a ghostwritten article promoting the drug. He left the committee in 2010 to join the Project on Government Oversight, a nonprofit watchdog organization.
From 2012 to 2014, Thacker completed two fellowships at Harvard University’s Safra Center for Ethics.
In July 2021, Thacker presented his arguments for the lab leak hypothesis origin of COVID, despite abundant evidence to the contrary (see Origin of SARS-CoV-2).
Thacker received the 2021 British Journalism Award for Specialist Journalism for a series of articles in The BMJ investigating undisclosed financial interests among medical experts advising the US and UK governments on vaccines. The award judges said “[t]his was expertly researched and written journalism on a subject of huge national importance.” The Association of British Science Writers chose an article Thacker wrote on Pfizer as a finalist for the Steve Connor Award for Investigative Science Journalism.
Thacker has been persistently critical of organizations that seek to identify disinformation and dampen its influence. One of the roles of the organization Center for Countering Digital Hate (CCDH) is to identify and quantify the amount of hate speech present on X/Twitter. Once the hate speech was identified, Elon Musk engaged in litigation against CCDH. This lawsuit was ultimately tossed out by a federal judge. Thacker expressed his support of Musk's side of the case.
In August 2024, Thacker criticized infectious disease physician and researcher Peter Hotez's statements in regard to anti-science aggression, which is Hotez's general term referring to science denial, the antivax ecosystem, and all forms of physical aggression against scientists who deliver this message. Thacker was specifically critical of Hotez's call for institutional assistance in supporting the message of vaccine researchers, labeling it as "Police Deployment against "Anti-Vaxxers"". This report, however, leaves out the context that Hotez has received threats credible enough to require police protection, including harassment occurring at Hotez's home address.

## Anti-vaccine reporting

In November 2021, The BMJ published a piece by Thacker alleging there has been "poor practice" at Ventavia, one of the companies involved in the phase III evaluation trials of the Pfizer vaccine. The report was enthusiastically embraced by anti-vaccination activists. Questioning Thacker's work in Science-Based Medicine, David Gorski wrote that his article presented facts without necessary context to misleading effect, playing up the seriousness of the noted problems. Some experts have expressed skepticism over the allegations made in the report. Prominent vaccination expert Paul Offit has criticized the issues outlined in the report as being vague and has cautioned against assuming the claims made in it are true.
In a 2023 article in Politico about Robert F. Kennedy Jr.'s history of endorsing conspiracy theories, Thacker is described as an "anti-vaccine reporter." Medical doctor David Gorski referred to Thacker as a "conspiracy-monger." The American chapter of the British charity Sense about Science, which promotes public awareness of science, noted Thacker's collaboration with anti-vaccine activists and referred to his work as "pseudo journalism."
In March 2025, Michael Hiltzik at the Los Angeles Times criticized "right-wing vaccine critic" Paul Thacker for mischaracterizing a vaccine study by Akiko Iwasaki from Yale University. Published on his blog, The Disinformation Chronicle, Thacker claimed that the Yale study showed that "long COVID patients may actually be vaccine injured." Iwasaki responded, "No. This is not what our study shows." Reuters also criticized Thacker's article, labeling it "misleading." For Bloomberg News, science columnist Faye Flam reported that pulmonologist Dr. Adam Gaffney of Harvard Medical School said that "the antivaccine community is ecstatic about this study because they think it validates their favorite pseudoscientific theory" regarding Long COVID.

## Allegations of Harassment

Neurologist Dr. Steven Novella claims that Thacker has "espoused anti-GMO views to the point of harassing GMO scientists." This claim is supported by another from a middle school teacher who says he was forced to temporarily shut down a Facebook page called "We Love GMOs and Vaccines" after Thacker began harassing one of his 12-year-old students. NYU journalism professor Keith Kloor said Thacker was a "once promising journalist who became a sadistic troll." These accounts are consistent with Thacker's own argument, which according to the Union of Concerned Scientists, is that "harassment is a price worth paying for transparency."