Legal Argumentation


This unit offers an in-depth study of some of the most important types of legal argument (good as well as bad) as applied in actual practice. Students will both (a) develop their ability to identify, reconstruct and critically analyse each of these types of argument (always based on the discussion of real judicial decisions) and (b) acquaint themselves - and engage critically - with the relevant jurisprudential literature on the justification of legal decisions and conclusions.

General characterization





Responsible teacher

Luís Duarte de Almeida


Weekly - 2

Total - 24

Teaching language



Not Applicable


There is no set textbook for this curricular unit. At the start of the semester, reading lists will be made available with recommended readings for each point on the syllabus.

Teaching method

Seminars. Each session will deal with a different point of the programme. For each topic there will be specific reading materials and excerpts of judicial decisions (accompanied by questions and exercises), which the students will be asled to read, and whose discussion they will be asked to prepare, in advance of class.

Evaluation method

Final exam (3 hours). 


During the semester (and if the number of students allows it), students will have the opportunity to (a) present, in writing, an analysis and critical reconstruction of an argumentative passage extracted from a judicial decision (selected by the coordinator of the curricular unit) and (b) orally discuss this analysis with the coordinator, in a public session. If the average classification obtained in both elements is positive, the student will be exempt from sitting the final exam, in which case that will be the final classification. If such students nevertheless decide to sit the exam, the final classification will be the highest between (i) the classification of the final exam and (ii) the average of the classification of the final exam and the classification obtained in the assessment described above. The exam is compulsory in all other cases.

Subject matter


  1. An introduction to argument analysis and reconstruction
  2. The fallacy of begging the question
  3. Arguing about fundamental legal positions
  4. Arguments from authority in law
  5. Arguments "ad absurdum"
  6. Arguments "a contrario"
  7. Arguments "a fortiori"
  8. The use of disjunctions in legal argumentation
  9. "Hume's law" and the justification of normative conclusions
  10. Arguments by analogy
  11. Inductive and abductive arguments in law
  12. The legal syllogism and the justification of law-applying decisions