Innovation has long been seen as a key responsibility of the American states. This may be puzzling, since a straightforward definition does not mark innovation as normatively good or bad. Innovative policy is simply whatever has not been tried before. It is different: different from the status quo, from policies of the past, and from the choices of any other government. Given this meaning, an innovation itself is not necessarily an advance.

Yet while each individual attempt at creating original policy may not improve society, a system that encourages the production of many innovations in different governmental units can lead to ultimate progress. The American federal system provides an opportunity for such beneficial innovation. If state legislatures have the capacity to craft inventive policy solutions, they can implement them at relatively little risk to the nation as a whole. Other states can observe whether or not their experiments are successful before deciding whether to replicate them on a larger scale. This is precisely the logic laid out by Justice Louis Brandeis in a quote that has become inseparable from the discussion of policy innovation: