Defining the burden of proof in conservation

Conservationists often must take action in the face of uncertainty about the costs and benefits of different options. Although this uncertainty can be paralyzing when the stakes are high, there is obviously a cost to inaction as well as action, and decision makers need to be encouraged to act when appropriate. Many other fields of human endeavor such as law, medicine, and public safety have formally developed the “burden and standards of proof” that decision makers have to meet in choosing to take action. In this paper, we review the standards developed in these other fields to help define a similar framework for conservation. Specifically we propose that a conservation decision maker must assume the burden of proof when there is a decision to act that substantially affects others, in which the decision maker has professional standing, where there is not immediate urgency, and where there is some, but not complete certainty about the outcomes of acting versus not acting. Once these initial tests have been met, in situations in which the decision maker is more worried about the consequences of not acting, then a relatively low standard of proof is required for taking action. If the decision maker is concerned with the consequences of acting in error, but the action is relatively reversible, then a medium standard of proof is required. And finally, if there are concerns about the consequences of acting in error, but the action is relatively irreversible, then a high standard of proof is required.