Rachel Herdy, 18 October 2016, 11h

October 18, 2016

ArgLab Research Colloquium

Av. de Berna 26, I&D Building, Ground floor, room 0.06


Fallacious Appeal to Expert Opinion in the Judicial Context

Rachel Herdy, Universidade Federal do Rio de Janeiro, Brazil


Criteria for evaluating argument from expert opinion are crucial in decision-making scenarios that involve conflicting testimonies, such as the courtroom. The judicial decision-maker needs help in order to decide between the legitimate and the fallacious use of argument from expert opinion. The objective of this presentation is twofold: understand the structure of a judicial argument from epistemic authority; and then evaluate its use in a specific argumentative practice.

The first part is analytical and will examine the different forms of appeal to authority – epistemic and administrative. I want to explore the argumentative schemes and critical questions involved in both forms of argument from authority (Walton, 1997), and consider their appropriateness when applied to the judicial context (Walton, 2016). In doing so I will also consider the treatment of authoritative reasons in Legal Theory (Raz, 1978; Hart, 1982). I believe that this interdisciplinary approach to the problem of authority will provide a more informed view of what is involved in the judicial appeal to expert opinion. I want to suggest that, in respect to the judicial context, while the appeal to administrative authority involves preemptive and content-independent reasons for action (or decision to obey the rule), an appeal to epistemic authority is dependent on the content of the assertion.

The task of clarifying the various factors involved in the evaluation of the different forms of argument from authority will be taken as a preliminary step toward an examination and evaluation of the appeal to expert opinion in the practices of the Brazilian Supreme Federal Tribunal. And so, the second part of this presentation will draw on empirical data obtained from an investigation of Brazil’s highest court current practice of appealing to experts. Appeal to experts in the courtroom frequently takes the traditional form of a witness testifying orally, under oath, and according to strict procedural rules of admissibility and evaluation (Haack, 2015); or it can consist in information directly cited by the parties or their amici curiae in briefs and memorials (Schauer and Wise, 2000; Larsen, 2012).

My investigation will focus on a quite peculiar argumentative practice that has been employed by Brazil’s highest court since 2007. It consists in conducting public hearings – an argumentative practice typical of the legislative setting – where experts present their findings to judges on a nationally broadcasted and non-dialogical context. This is a work in progress; however, a critical evaluation of the partial results collected up to now suggests a fallacious use of the appeal to expert opinion in the Brazilian Supreme Federal Tribunal's practice of conducting public hearings.



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