In late October, as Tasmania began reviewing its ban on genetically modified (GM) food crops, a group of 97 scientists signed a joint statement that warned: “The claimed consensus on GM organism safety does not exist.”

Within a fortnight the number of signatures had risen to 231. Elsewhere, 828 scientists had jointly called “for the immediate suspension of all environmental release of GM crops and products.”

Their concern is in part a response to the ritual shamings that scientists are subjected to when their controversial findings challenge official GM doctrine.

These shamings are rife in Australia. Earlier this year, a team led by Flinders University epidemiologist and biochemist Adjunct Associate Professor Judy Carman published a peer-reviewed toxicology study that found pigs fed GM maize and GM soy suffered organ damage compared with the control group of pigs.

These findings aligned with a 2005 CSIRO GM field-pea study that suggested the GM process may create novel proteins and sugar-chains that can be allergenic or toxic.

But the study went largely unreported, and Dr Carman — like CSIRO’s Maarten Stapper, WA’s Department of Agriculture’s Patrick Fels, and others before them — endured the public smearing scientists face when their findings challenge official GM doctrine. Even before release, her team’s findings were branded “junk science”. “pseudoscience” and “bad science” by agritech spokespeople and scientists. (Carman answers her detractors here.)

Science sociologists Professor Brian Martin and Dr Sandrine Thérèse call these shamings “degradation rituals”. In these rituals, methodology once considered the gold standard is routinely recast by opposing scientists as ‘flawed’ or ‘junk science’ in the case of controversial findings.

Still, Dr Carman appeared on ABC Radio, where she told listeners that such feeding studies are not required by FSANZ (Food Standards Australia and New Zealand), which relies on industry data for its safety assessment of GM foods. In turn, Carman’s study was immediately dismissed by FSANZ and the GM industry it regulates.

As Tasmania reviews its bans on GM crops this month, GM advocates have been appearing in force in news media and opinion sites. In The Conversation, scientists David Tribe and Rick Roush portray those who criticise GM foods as “anti-science” and “anti-GM extremists” who are “rejecting science”.

Similarly, CSIRO’s corporate communications advisor Craig Cormick claims that those who support GM foods tend to be “pro-science” while those who reject GM “have tendencies towards conspiracy theories”.

These claims are not evidence-based.

First, as the new joint statements make explicit, there is no scientific consensus on the safety of GM products.

Secondly, scholarly studies including Swinburne University’s National Technology and Society Monitor consistently find that although Australians have “high levels of trust in science”, most remain sceptical of the benefits claimed for GM products and are concerned about the multinational industries and regulations surrounding these.

Many support GM technologies in medicine but not in our food chain.

Yet GM advocates frame their position as scientific consensus against public ignorance: “Scientists internationally are outraged,” write Roush and Tribe, at “unethical anti-scientific” opposition to GM products. In Fairfax newspapers, Nicolle Flint asserts: “Extensive research exists proving the safety and environmental benefits of GM crops based on scientific fact, not emotion.” In The Tasmanian Times, Jan Davis writes: “The science is settled.”

Many geneticists, toxicologists, agronomists, epidemiologists, biochemists and public health scientists disagree, but most, reports Scientific American “have chosen to remain anonymous for fear of reprisals.”

Most scientists who have conducted independent studies that suggest risks from consuming or growing GM products have their findings routinely ridiculed by biotech industry scientists and spin doctors, and dismissed by the public bodies that regulate them.

The problem is deep-rooted. “Agritech companies have given themselves veto power over the work of independent researchers” by denying access to GM seeds, reports Scientific American. It continues:

    …only studies that the seed companies have approved ever see the light of a peer-reviewed journal. In a number of cases, experiments that had the implicit go-ahead from the seed company were later blocked from publication because the results were not flattering.

“It is not always simply a matter of blanket denial of all research requests,” said Cornell University’s entomologist Elson J. Shields, “but selective denials and permissions based on industry perceptions of how ‘friendly’ or ‘hostile’ a particular scientist may be” toward GM technology. In her introduction to the Australian edition of Genetic Roulette, with contributions from thirty scientists, Rosemary Stanton OAM reports the same problem.

Those few studies that against the odds are permitted, funded and peer-reviewed but have negative results are routinely dismissed as “inconclusive” by GM industry scientists and government regulators. To be conclusive, studies must be repeated, which takes political will and funding, as the GM industry doesn’t repeat studies that show evidence of adverse effects. (An ostensible exception is CSIRO’s GM field-pea, which has undergone millions of Euros worth of repeat studies, the findings of which are mixed.)

So when regulators take a weight-of-evidence approach to declare safety or benefit, the scales tend to favour studies that take political will or industry funding.

Consequently, negative studies tend to be sidelined in media because of a putative ‘consensus’ on safety and benefit. For instance, recent research published in the peer-reviewed International Journal of Agricultural Sustainability finds that GM crops have lower long-term yields than non-GM crops. The study concurs with a handful of previous findings that GM crops have led to an increase in overall pesticide and herbicide use. These results remain under-reported and dismissed, while studies with positive results continue to dominate rural media.

The famously flawed peer review process (like democracy, the ‘least-worst’ system we have) cannot address these systemic problems. Asymmetry in scientific debate is a vexing issue for those of us troubled by the way the climate change debate played out, in which a small number of scientists and lobbyists, some with fossil-fuel funding, achieved disproportionate coverage for their claims. The number of pro-GM scientists and lobbyists are far greater, but they also tend to work with organisations or research projects that lean on industry partners.

This is not to suggest conspiracy or wilful dishonesty among industry-supported scientists, but to acknowledge the well-documented evidence that industry-backed research is far more likely to produce findings and doctrines favourable to industry.

Science does not exist in an apolitical and unproblematic realm. By ignoring inconvenient evidence and claiming scientific consensus, the lobbyists and regulators alike are promoting ideology over a more scientific approach to truth.

• An earlier version of this article was first published in New Matilda.

Katherine Wilson is former co-editor of Overland and a PhD candidate at The Swinburne Institute for Social Research. Her thesis is in the field of material cultural studies. She has a special interest in the politics of contested biosciences.