Environmental public policy tools aim to impact consumer behavior. Nevertheless, the causal relationship system between the implementation of a public policy and behavior is full of disconnections. Thus, it should be deepen with the combined analysis of public policies and consumer decision process. Indeed, this latter also depends on others psychosocial determinants towards behavior and other contextual forces. The impact of public policy tools need to be distinguished among them. Our study on the French environmental public policy aimed at acquiring low-carbon emission cars focuses on understanding the impact of public policy tools on consumer buying decision process. Indeed, the attitude towards public policy tools affects consumer decision process. It results that the impact is not so direct but it moderates the relationship between the main determinants of behavior. These moderation effects depend on the psychological or structural nature of the public policy tools which impacts specific relationships of the consumer decision process.
