We propose an activity-generating theory of regulation. When courts make errors, tort litigation becomes unpredictable and as such imposes risk on firms, thereby discouraging entry, innovation, and other socially desirable activity. When social returns to innovation are higher than private...

We ask whether regulation can usefully supplement litigation in a model of optimal social control of harmful externalities. In our model, firms choose activity levels in addition to precautions. In contrast to the usual analysis, we assume that social returns to activity are higher than private...