There is now a relatively well-developed critique of the application of cost-benefit analysis (CBA) to environmental problems. Theories of deliberative democracy have been invoked which question the individualistic, preference-based calculus of CBA. While the critique of CBA is well developed, the positive accounts of the virtues of deliberation appear relatively sketchy. This is a very large task, but the paper argues one important aspect of it can be captured by the following question: What are the relative merits of public deliberation about the environment, vis-a-vis private reporting of individual judgements? The paper addresses this question by seeking to analyse in detail the virtues of discussion in one widely debated deliberative institution, the citizens' jury. Throughout, the paper draws on the experience of a citizens' jury on an environmental problem: a jury on wetland restoration in East Anglia, UK, co-organized by the author.

The aim of this research is to determine whether people in the UK associate genetically modified food (GM food) with the ‘mad cow’ disease (or BSE) issue, and explain any such association in terms of analogical reasoning. Further, to test whether a lack of perceived ‘control over exposure’ to GM food accounts for the heightened vulnerability it is typically associated with. Two consecutive questionnaires were administered in various regions of the UK. The first asked 200 participants to indicate whether they regarded GM food as a health risk, and to spontaneously identify issues similar to GM food. The second asked a further 200 to rate the similarity between GM food and BSE, Salmonella, and food irradiation, and to give personal and general risk ratings for consuming GM food, and tolerance ratings for its availability and availability if ‘always clearly labelled’. The results indicate GM food is overwhelmingly identified as a health risk, and that BSE is widely held to be analogous with GM food. However, BSE was rated as less similar to GM food than food irradiation. The widespread identification of BSE as an analogue is explained in terms of it representing a ‘worst-case scenario’. The risk ratings are consistent with the heightened sense of vulnerability associated with GM food; the tolerance ratings are greater for the availability of GM food if ‘always clearly labelled’, indicating a perceived lack of control over exposure to GM food accounts, in part, for GM food risk perceptions. However, the results also indicate that, in terms of practical risk management, labelling may only be effective with respect to a younger age group.

Climatological and agricultural research has shown that El Nino cycles in the Pacific Ocean are a good predictor of maize yields in southern Africa, particularly Zimbabwe. However, forecasters can only offer probabilistic predictions, rather than saying with certainty whether Zimbabwe will experience wet or dry conditions. In an effort to avoid confusing farmers, extension service officers translate the forecast into deterministic terms. This approach conflicts with the literature in risk communication, which suggests that participatory discussions of the full forecast content is necessary to maintain credibility over time. But most of the research on which this literature is based has taken place in industrialized countries, and it is unclear whether the lessons apply as well in places like rural Zimbabwe. To test for this, an experiment was conducted with farmers in villages throughout Zimbabwe, in which they revealed their ability to make decisions under situations of uncertainty. The results are qualitatively similar to those of similar experiments conducted in industrialized countries. This suggests that improvements could be made to current forecast communication practices in Zimbabwe.