Rationale and explanation differ in the viewpoint. Both of the words have Latin origin. While rationale is the process by which one arrives to a conclusion, explanation means to clarify something in order to make it clear. Rationale is about logic and reasoning, while explanation is about meaning, interpretation, the basis or fundamental reason of a phenomenon. In legal context, rationale means a discussion of the reasons behind how a decision was made. This kind of document discusses the reason of choice, how it was developed, what assumptions were used and why the conclusion is realistic. In legal context, the meaning of explanation is not different from its general meaning.
