  Democracy often fails to meet its ideals, and these failures may be made
worse by electoral institutions. Unwanted outcomes include polarized
institutions, unresponsive representatives, and the ability of a faction of
voters to gain power at the expense of the majority. Various reforms have been
proposed to address these problems, but their effectiveness is difficult to
predict against a backdrop of complex interactions. Here we outline a path for
systems-level modeling to help understand and optimize repairs to U.S.
democracy. Following the tradition of engineering and biology, models of
systems include mechanisms with dynamical properties that include
nonlinearities and amplification (voting rules), positive feedback mechanisms
(single-party control, gerrymandering), negative feedback (checks and
balances), integration over time (lifetime judicial appointments), and low
dimensionality (polarization). To illustrate a systems-level approach we
analyze three emergent phenomena: low dimensionality, elite polarization, and
anti-majoritarianism in legislatures. In each case, long-standing rules now
contribute to undesirable outcomes as a consequence of changes in the political
environment. Theoretical understanding at a general level will also help
evaluate whether a proposed reform's benefits will materialize and be lasting,
especially as conditions change again. In this way, rigorous modeling may not
only shape new lines of research, but aid in the design of effective and
lasting reform.

General Economics;Economics