that range from paralysis by endless deliberations to reaching only trivial results when trying to accomplish a consensus among stakeholders with conflicting values and interests (e.g., Sunstein, 2001, 2006). As Ventriss and Kuentzel (2005:520) state: “a consensus in the public sphere is like a transitory mirage, contingent on the constellation of actors who happen to rise to the surface of ongoing public conflict and debate.”
It is useful to recognize at the outset that decision making on matters of environmental policy is intrinsically and appropriately a political process (Cortner and Shannon, 1993; Landy, 1993; Williams and Matheny, 1995). Environmental decisions always involve both public and private interests. Furthermore, the decisions are typically backed by governmental authority, so environmental policy always involves power relations in society. Such relations shape environmental policy, and environmental policy in turn reshapes power (Stirling, 2008). This recognition provides a context for understanding participation processes, the motivations for public participation, and the challenges to it.
Science plays a special role in public participation in environmental issues. Environmental policy decisions therefore should be—and in the United States by statute typically must be—informed by the best available scientific information and judgments. Because they are matters of public policy they should—and, again by statute, typically must—also take into account the knowledge, values, and preferences of interested and affected parties. Ideally, public input and good information and judgment are complementary. Interested parties can bring critical factual information and scientific analyses to the process, whether as scientists themselves, by employing scientists, or by contributing experiential, observational or traditional knowledge. Similarly, scientific analysis can be made more decision relevant when public values and concerns frame the questions being asked and the methods deployed. Ideally, thoughtfully structured public participation can make these choices explicit and examine their implications for public decisions. Scientific analysis on its own is an inadequate guide to determining how the risks, costs, and benefits of environmental decisions ought to be balanced or how they should be distributed across the public. Such decisions depend not only on factual information, but also on values and preferences and on interpretations of factual information (e.g., National Research Council, 1983, 1994, 1996). Even setting the policy agenda—deciding which environmental matters deserve public consideration and which do not—requires the integration of scientific analysis and public input. In a democracy, such decisions cannot legitimately be made without consulting the many groups in society. When the issues are of great significance and complexity, a democracy would be foolish to forego good science.
However, the best ways to pursue the ideal of integrating scientific analysis, values, and judgment and the extent and manner in which the