ABSTRACT
Many regulatory situations involve a choice between intervening before the activity that involves some social harm takes place – an ex ante control – versus dealing, ex post, with the consequences of the activity. Often, a combination of ex ante and ex post approaches (or, employing the terminology of John Stuart Mill, preventive and punitory approaches) is adopted. Speed bumps are placed on some roads, though apprehended speeders will also be fined (in addition to the potential damage to their vehicles). Safety features are mandated for certain consumer products, at the same time that manufacturers may be liable for injuries caused by products that satisfied the mandates. Private behavior frequently involves ex ante measures, as Hobbes pointed out, despite the availability of ex post public enforcement.
