What ethical principle supports the fair treatment of all investors?

The ethical principle that primarily supports the fair treatment of all investors is justice. Justice emphasizes the importance of fairness and equity in the distribution of resources, rights, and responsibilities. In the context of investing, it means that all investors should have equal access to information, opportunities, and treatment without any favoritism or discrimination. This principle is crucial in maintaining integrity in the financial markets and helps to build trust among investors.

Justice encourages firms and professionals to uphold ethical standards that protect the interests of all stakeholders, ensuring that no individual or group is unduly disadvantaged. This is particularly relevant in regulatory environments where equity in treatment can foster a more inclusive and competitive market.

While other principles such as equity, transparency, and accountability also play vital roles in ethical finance, they do not singularly encapsulate the overarching idea of fair treatment like justice does. Equity relates more to fairness in outcomes, transparency focuses on openness and clarity in actions, and accountability pertains to being answerable for one's actions. Each of these is important in its own right, but justice is the principle that most directly addresses the notion of fairness for all investors.