In the case of Crowd Sourcing, the idea is to represent the different opinions, that are certainly conflicting, through formal arguments (Argumentation theory).  After that, we can use an aggregation method (from Decision analysis) in order to find a compromise and build a recommendation.   How to present now the recommendation or the issues to the general public we can construct formal explanations (based on the previous arguments). Indeed, justifying and explaining a rationale for a decision is almost as important as the recommendation itself.  This is particularly true in situations where the decision needs to be justified to some other stakeholders (who did not participate to the decision process).  Explanation can help: to understand the reasoning steps and data behind recommendations, to Increase the public’s acceptance of the recommended choices and to have transparent decision.