Iudex non Calculat?

Mass harm situations caused by corporate misbehaviour, defective products, harmful pharmaceuticals, accidents or environmental disasters nowadays multiply and create new challenges for legal actors and society at large. In its 2013 Recommendations, the EU Commission highlighted that ‘a key role should be given to courts in protecting the rights and interests of all the parties involved in collective redress actions as well as in managing the collective redress actions effectively’. The role of judges therefore turns out to be essential: they are expected to behave as watchdogs scrutinizing the overall admissibility of mass claims, as active case managers ensuring that cases make orderly progress, and as shepherds ensuring that all interests at stake are sufficiently protected. A key issue to be explored remains the influence of the mass context on decision-making which may potentially lead judges to depart from policy makers’ expectations. Interestingly, the mass context is nowadays an element often discarded by judges themselves. Yet, in the context of mass litigation, cases involve and consolidate in one lawsuit hundreds of represented claimants who have suffered a similar harm. The magnitude of the case - that is the number of people involved and/or the size of the loss at stake – is therefore likely to be considerable. Even though judges discuss and exchange with a limited number of protagonists during hearings – e.g. with representative bodies such as associations or leading counsels – judges must preserve the interests of absent parties. Behavioural studies have shed important light on ways groups are perceived by external observers, and on the impact of number and size on information processing. By investigating in greater details the effects associated with the case magnitude on decision-making, this paper aims at providing an alternative viewpoint on the issue of collective redress which will be of particular interest for courts and regulators at both national and European levels.