Legal
scholars have debated the impacts of government policy for millenia.
In 81 B.C., Chinese scholars argued about the desirability of monopolies
in the salt and iron industries in a succession of essays and public
debates. These debates were theoretical—with scholars
predicting the positive and negative effects of monopolies as compared
to a competitive market. Over two thousand years later, theoretical
debates over policies remain the norm. But theory alone cannot
resolve many policy issues because different theories point in different
directions. Scholars attempt to inform these debates by parsing
historical data, but regression analysis of policy is fraught with complications.
There is little policy variation on many topics of national importance,
and the variation that does exist is correlated with many other factors.
Empirical policy evaluation often resembles a drug study in which the
experimental population does not receive an assigned treatment and instead
gets to choose whether to take the medicine or the placebo.
Policymakers
and commentators frequently refer loosely to new laws and legal institutions
as “experiments,” but in contrast to
medical experimentation, these innovations
rarely randomly designate treatment and control groups. There
have been a handful of exceptions since 1968, including randomized “social
experiments” that were performed to assess the impact of government
policies. But the legal literature
has virtually ignored them. Legal scholars have discussed the
results of particular social experiments, and they have
commented occasionally that additional social experiments could provide
useful information in one field or another.
But these legal scholars have not addressed the normative question of
whether the legal system should generally seek to incorporate experimental
methods, and if so, what approaches the legal system should take to
maximize the chance that experiments will improve policy.