Class Membership in Class Actions : An Experimental Study

Prior research suggests that class membership is higher in opt-out models than in opt-in models. One of the main concerns with an opt-out model is that it causes a tension with the principle of party autonomy (litigant autonomy). This study explores this tension as well as whether an opt out procedure can enhance party autonomy rather than limit it. In two experiments, it is tested whether the size of the class is impacted by the procedure (opt in/opt out) in combination with (1) the size of the loss and (2) knowledge of the settlement outcome when deciding to opt in or opt out. The results provide support for the idea that an opt-out model does not necessarily put restraints on individuals' decision making and that it can even enhance party autonomy