William Sutherland and colleagues' 20 tips for non-scientists on how to interpret scientific evidence could do more harm than good in the hands of policy-makers (Nature 503, 335–337; 2013).

My experience in natural-resource management taught me that emphasizing uncertainty can lead policy-makers to dismiss evidence rather than to embrace it. On one occasion when I testified before Congress, I was told to come back only when I was 100% certain of my information. Practically speaking, this might be viewed as an excuse for political inaction.

For policy-makers, assessing the potential risks and benefits of policy action or inaction should be critical. For instance, when scientific uncertainty about the likelihood of a severe weather event is high but the consequences are potentially dire, there is a large risk in taking no protective action.

Rather than trying to teach non-scientists how to interpret uncertainty in our results, let's do a better job of helping them to understand the possible consequences of what they do or don't do.