Randomised Badger Culling Trial (RBCT) publications update

Following on from our blog of September 23^rd 2024, that reported on the uncertainties around the RBCT analyses, we are pleased to provide an important update. As Jane Dalton writes in The Independent, “Bombshell’ badger cull study review ‘disproves evidence’ used by governments to justify killings.”

A quick reminder of why the RBCT is so important

Government badger cull policy has rested all but entirely on the RBCT analyses. It is the science that DEFRA has used to create policy and in court to defend their decisions to experiment with badger culling. The RBCT claimed badger culling can reduce bovine TB in cattle; very many subsequent studies are heavily derived from it.

Disease benefits that have in recent years been ascribed to badger culling by civil servants and politicians are in reality, far more likely due to implementation of additional cattle measures that were put in place before or at the same time as culling. But Government scientists continue to infer that badger culling has caused a reduction in disease, simply because this is what was “predicted” by the results of the RBCT. its classic confirmation bias.

Below is a chronology of some key RBCT publications.

16^th February 2006, “Positive and negative effects of widespread badger culling on tuberculosis in cattle” was published in Nature by Donnelly et al.

10^th May 2019, “Badger Culling and Bovine TB in Cattle: A Re Evaluation of Proactive Culling Benefit in the Randomized Badger Culling Trial” was published in the Journal of Dairy and Veterinary Sciences by Tom Langton.

13^th December 2022, First version of “Absence of effects of widespread badger culling on tuberculosis in cattle” was posted as a preprint on Research Square by Torgerson et al..

15^th July 2024. “Absence of effects of widespread badger culling on tuberculosis in cattle” was published in Nature Scientific Reports by Torgerson et al.

18th August 2024. Interim report on the August 2024 pre-publication response to the July 2024 re-evaluation of evidence and analyses of proactive culling (published in 2006), as a part of the Randomised Badger Culling Trial (RBCT), 1998-2005. Independent pre-publication report on the Mills et al. papers to be published on 21.08.2024.

21^st August 2024. “An extensive re-evaluation of evidence and analyses of the Randomised Badger Culling Trial (RBCT) I: Within proactive culling areas”  and “An extensive re-evaluation of evidence and analyses of the Randomised Badger Culling Trial II: In neighbouring areas” were published in Royal Society Open Science by Mills et al..

16^th September 2024. A ‘Comment’ response to the new Mills et al. 2024 papers was submitted to the Royal Society Open Science: “Randomised Badger Culling Trial lacks evidence for proactive badger culling effect on tuberculosis in cattle: comment on Mills et al. 2024, Parts I & II” by Torgerson et al.. This was pre-printed with bioRxiv on 20th September.

11^th June 2025, ‘Comment’ response to the two new Mills et al. (2024) to the Royal Society Open Science was published: Randomised Badger Culling Trial—no effects of widespread badger culling on tuberculosis in cattle: comment on Mills, Woodroffe and Donnelly (2024a, 2024b),  by Paul Torgerson et al. (2025), Royal Society Open Science.

Inexplicably, the Natural England rationale for licensing the supplementary badger culls in 2025 year did not take the Torgerson et al 2024 preprint into consideration. This is despite considering un-peer reviewed reports this year, and preprints (notably Mills et al 2024) last year.

So although the peer reviewer (Prof M. Brewer, Director of Biomathematics and Statistics Scotland) of Torgerson et al (2025) favours this new evaluation, which concludes that “The justification for lethal control of badgers to date appears to have been based upon basic statistical oversight.”, it was not considered in the cull licensing for 2025. The peer review comments for the new Torgerson et al. Comment paper are available from the online link, and are well worth reading in full.

The justification for badger culling has been shown to be wrong in so many ways. Badger culling must stop immediately, on the basis of scientific evidence.