Laypeople have difficulty processing efficiency when assessing environmental policies

What should mostly matter is how successful environmental policies are at satisfying citizens’ policy preferences (e.g., reducing carbon emissions), relative to the policies’ cost. Yet, across 6 studies ( N = 2759, 2 pre-registered), we found that French citizens tended to be rather insensitive to policy efficiency. In Experiments 1a–d ( N = 854), citizens regarded an environmental policy driven by an altruistic intention that turned out to be inefficient as being more commendable than a policy motivated by selfishness that dramatically reduced carbon emissions. In Experiment 2 ( N = 1105), altruistic but low efficiency policies were supported only slightly less than selfish but highly efficient policies. Independent manipulation of intent and efficiency indicated low sensitivity to large differences in efficiency expressed numerically, and substantial sensitivity to actors’ intentions. Moreover, moral commitment predicted stronger support for any environmental policy addressing the issue, regardless of its efficiency. Finally, Experiment 3 ( N = 800) found that introducing reference points and qualitative appraisals of a policy’s impact and financial cost can nudge participants towards greater attention to its efficiency. Our paper highlights the importance of using contextual and qualitative (vs. numeric) descriptions of policies to make citizens more focused on their efficiency.