Optimal Taxation, Environment Quality, Socially Responsible Firms and Investors Available to Purchase

We characterize the optimal pollution-, capital- and labour-tax structure in a continuous-time model in the presence of pollution (resulting from production), both in the first-and second-best, allowing investors to be driven by social responsibility objectives. The social responsibility objective takes the form of warm-glow, as in Andreoni (1990) and Dam (2011), inducing firms to reduce pollution through increased abatement activity. Among the results, the second-best pollution tax displays an additivity property and the Chamley&Judd zero capital-income tax can be violated under warm-glow preferences. We also show that first- and second-best pollution taxes are positive, under warm-glow preferences, and, under mild assumptions, the latter yield lower first-best pollution taxes and lower pollution intensity.