The illegal or unethical behaviors that business ethics treats are often produced by group dynamics rather than by private motives. This paper aims to introduce points of view of social or collective psychology into business ethics in order to analyze the unethical collective behaviors, and propose the means of keeping an organization ethical. We will focus especially on the structure and the process of communication inside and outside the organization. In the first section, we will discuss the relationship between communication and ethics from a general and philosophical point of view. In the second, we will suggest that the Autopoiesis theory fits to describe how ethical or unethical state of an organization emerges. In the third, we will try to make clear the process that produces the ethical consciousness that is necessary to prevent organizational injustice from a psychological approach. In the final section, we will present an ethical scale that we are developing in order to measure the ethical level of an individual or an organization.