The next post office scandal? How flawed science justifies the slaughter of a "protected" species

Imagine this: for decades, an entire government policy causing mass death is founded on evidence that many scientists now say is deeply flawed. Like the infamous Post Office scandal, where innocent workers were blamed for crimes they didn’t commit, the badger cull hinges on a narrative that points the finger at badgers for spreading bovine tuberculosis (bTB) to cattle. The result? Over 230,000 badgers, a protected species, slaughtered since 2013 in what some researchers are now calling an unnecessary and misguided campaign.

The story began in 1971 when a Gloucestershire farmer handed a single badger infected with bTB to local officials. Fast forward 50 years, and the scene is horrifying: tens of thousands of badgers killed annually, their bodies stacked in skips and bins, with no testing to confirm whether they carried the disease. How did England get from one infected badger to a full-scale assault on this species? The answer lies in the Randomised Badger Cull Trial (RBCT)—a pivotal field experiment carried out between 1998 and 2007.

Analysis of the RBCT findings claimed that killing badgers reduces bTB in cattle in cull areas, though it increases infections in surrounding areas due to badger dispersal. These conclusions have heavily shaped government policy, justifying widespread badger culling since 2013. But recent reanalyses of the RBCT data have exposed critical flaws, leading researchers to question its conclusions and the entire basis for badger culling.

The RBCT: Shaping a Controversial Policy

The RBCT was designed to test the relationship between badgers and bTB. It divided 10 trial areas into three groups, commonly called "triplets." In one area, badgers were proactively killed in large numbers. In another, badgers were killed reactively—only when bTB outbreaks occurred in local cattle herds. The final area served as a control, where badgers were surveyed but left undisturbed.

The reactive killing was quickly abandoned after reports suggested it increased bTB outbreaks in cows compared to control areas. This left only the proactive culling and control groups in the experiment.

In 2006, researchers published their analysis of the RBCT findings, concluding that proactive culling reduced bTB in cattle within cull areas but increased it in surrounding regions due to disrupted badger populations. This analysis formed the backbone of the government’s bTB strategy, leading to a large-scale culling program that has killed hundreds of thousands of badgers to date.

Revisiting the RBCT: Flaws in the Foundation

Recent reanalyses of the RBCT data, including a 2024 study published by Professor Paul Torgerson (British veterinary academic) and colleagues, have cast doubt on its conclusions.

Tom Langton was a co-author of the 2024 study. He is a well-known ecologist and expert on badger conservation who has long argued that the RBCT’s methodology and conclusions are deeply flawed. Langton has pointed to systemic issues in the design of the trial and the government’s interpretation of its results, which he claims have driven an unnecessary and ecologically damaging culling program.

Torgerson’s team attempted to replicate the RBCT’s findings using the same data and methods but failed. Reproducibility is a cornerstone of credible scientific research: if other researchers cannot replicate the findings using the same data and techniques, it calls the original conclusions into question. This inability to reproduce the RBCT’s results led Torgerson’s team to dig deeper into the analysis, revealing three critical flaws:

Photo by Vincent van Zalinge on Unsplash

Failure to Account for Key Variables:

According to Torgerson’s team, the RBCT analysis did not properly account for "exposure." This is the number of herds in the experiment (ie sample size) and the observation period. That is, the researchers did not use a denominator correctly. Analysis correcting for sample size and time at risk, i.e. using incidence rates, showed no significant trend that would link badgers to bTB rates in cows.

Overfitting Data:

Overfitting occurs when a statistical model tries to account for too many factors, resulting in skewed conclusions. Torgerson’s team found that the RBCT model relied on overfitted data, making its results less reliable.

Missing Key Data:

The RBCT failed to include all relevant data about bTB in cattle herds, further weakening its analysis. In particular, it only used data on the ‘confirmed’ presence of bTB – known as breakdowns – in cow herds, excluding the ‘unconfirmed’ ones. Despite what these labels suggest, unconfirmed breakdowns are instances where cows in herds test positive for bTB in robust tests, so they most certainly would have had bTB. They just lack other particular signs of bTB, which is why the original researchers excluded them. This too impacted the reliability of the analysis.

The Implications of Flawed Science

The flaws in the RBCT are more than an academic issue—they have real-world consequences. Based on these flawed findings, badgers have been vilified and slaughtered at unprecedented rates, with little to no testing to confirm whether they carry bTB. Meanwhile, research increasingly points to cattle-focused measures, such as stricter testing and biosecurity, as the most effective way to control bTB.

This controversy over the RBCT mirrors the scientific reproducibility crisis, where studies fail to yield the same results when reanalysed. If the RBCT’s conclusions cannot hold up to scrutiny, the entire justification for badger culling crumbles. Like the Post Office scandal, it raises an uncomfortable question: how many lives have been lost based on flawed evidence?

The Path Forward / petition to end the cull

Researchers and wildlife advocates argue that it is time to abandon the cull and focus on evidence-based measures to tackle bTB. The stakes are high—not only for badgers but also for maintaining public trust in science and policy. The badger cull stands as a stark reminder of the harm that can result when science is misused or misunderstood.

And it is for all the reasons outlined in this article that we recently submitted a new Govt petition calling for an immediate end to the badger cull and the adoption of other approaches to bovine TB control. An incredible 25,000+ of you have already signed it in just under 3 weeks. If you're reading this and you're as shocked and disgusted as we are about the continued slaughter of a protected species then please add your name here.