CHAPTER 3. What criteria for choosing environmental public policy measures? The carbon tax, the economists and the Yellow Vests[CHAPITRE 3. Quels critères pour choisir les dispositifs des politiques publiques environnementales ? La taxe carbone, les économistes et les Gilets jaunes]

For a large majority of economists, the carbon tax, legitimized by its theoretical foundations, should be at the heart of policies to combat climate change. However, as environmental economist Jean-Charles Hourcade already noted in 2015, "the transition from theory to practice is a difficult exercise when it comes to carbon taxes". We will first see why and how well-being economics came to consider efficiency as the sole criterion and how the carbon tax became a flagship measure for environmental economists. We will then see the difficulties they encounter when they try to reconcile the fundamentals with the demands of social and political realities at the time of implementing the measure. Finally, we will see how normative approaches which may have seemed relegated to the second rank of the discipline, mobilize these events to show the insufficiency of the criterion of effectiveness and the need to take into account ethical criteria in the choice of public policy instruments. .