In this article it is claimed that legal argumentation should part from principles contained in argumentation in general. Therefore, it should be adapted to argumentative criterions which take into account the logic component (as a product), rhetoric (as a process), and dialectic (as a procedure). The text parts from the analysis of these categories, and presents three moments: the first one deals with argumentation in general. The second one inquires about legal argumentation, which meets criterions, but given its specificity, contains special elements. Finally, a current problem is the type of argumentation in participative democracies. Through this topic we try to show that some standards are maintained for this field. In conclusion, it would be possible to evaluate legal argumentation according to rational principles, expressed in criterions of sufficiency, correspondence and pertinence, as well as in a code of good argumentative practices.