In general, an ethical argument can be structured in the following way.
Introduction: Establishes the ethical principle and states the essay’s thesis
Background: Gives an overview of the situation
Ethical analysis: Explains the ethical principle and analyzes the particular situation on the basis of this principle
Evidence: Presents points that support the thesis
Refutation of opposing arguments: Addresses arguments against the thesis
Conclusion: Restates the ethical principle as well as the thesis; includes a strong concluding statement