This study takes Japanese consumers as its subject and, from a micro-level perspective, explores whether there exists a behavioral chain in environmental behavior that extends from the willingness to pay (WTP) for electric vehicles (EVs) to the willingness to pay for carbon taxes. It further analyzes the key factors that may contribute to this potential linkage. By systematically integrating relevant studies and conducting quantitative analysis using partial correlation coefficients, the results indicate that demographic attributes such as gender and income, as well as cognitive variables like environmental awareness and interest or understanding of technology and policy, generally exert similar influences across both domains. In other words, these factors not only affect whether people are willing to purchase environmentally friendly products but also potentially influence their support for environmental policies. This finding to some extent supports the hypothesis of behavioral connectivity between green product adoption and institutional policy acceptance, based on demographic and cognitive factors. The study further proposes and partially verifies a psychological mechanism, suggesting that explicit green consumption behaviors may be translated into implicit acceptance of institutional policies. The results show that under certain social and cognitive conditions, visible pro-environmental actions can promote public acceptance of abstract policy instruments. However, current empirical evidence only supports a one-way transmission path from EV WTP to carbon tax acceptance; the reverse path, where consumer behavior is triggered by policy signals, remains to be substantiated in future research. The stability and generalizability of this behavioral chain are also subject to the specific variables and social context examined. From the perspective of behavioral economics, this study provides preliminary evidence on how consumer behavior can reinforce institutional environmental policies. It highlights the strategic importance of positioning consumers as key agents of policy compliance in the design of low-carbon transition strategies. At the same time, it offers a new perspective for promoting green products, suggesting that enhancing consumer environmental awareness and engagement can help facilitate broader policy acceptance, thereby fostering a synergistic pathway toward green transformation.