*Motivated by recent examples, this study addresses the instability of International Fishery Agreements (IFAs) through a dynamic multistage optimal control model involving two heterogeneous countries exploiting shared fishery resources. We explore the transition from cooperation to competition, driven by differing time preferences and the adoption of Markovian strategies post-withdrawal. Our results demonstrate that coalitions of heterogeneous players inevitably dissolve over time, regardless of the sharing rule. By applying the dynamic Shapley Value, we decompose the coalition’s aggregate worth, mitigating the incentive to exit. Furthermore, we find that a fishing moratorium policy can expedite the recovery of near-extinct fish stocks, with fishing resuming under cooperative management once sustainable levels are reached.

**This paper explores how morality influences political support for public policies by comparing outcomes in societies of conventional (self-interested) agents and those of Kantian agents. Our model features two public policies—a redistributive lump-sum transfer and a public good—with agents voting on both the tax rate that funds these policies and the distribution of the public budget between them. After the voting process, agents decide on their labor supply, and following taxes and transfers, they may choose to make voluntary contributions to the public good. The model incorporates morality through the Kantian categorical imperative, prompting agents to universalize the morally equivalent contributions of others when determining their own voluntary contributions. Using a probabilistic voting framework that aligns with utilitarian welfare maximization, we show that Kantian societies support lower tax rates and allocate a smaller share of the budget to the public good compared to societies with purely self-interested agents. This moral constraint on policy support leads to increased inequality in private consumption and consistently lower utility levels for all agents, with the most significant adverse effects on individuals with lower productivity. These findings reveal the complex trade-offs between morality and social welfare, highlighting the limitations of Kantian ethics in achieving distributive justice within democratic policy-making.