Why public choice?

By me, now out in the Routledge Handbook of Public Policy, edited by Eduardo Araral, Scott Fritzen, Michael Howlett, M Ramesh, Xun Wu. A snippet:

This essay describes some of the contributions to the study of public policy processes of those who have helped build that agenda. I start with two assumptions: that public choice offers some fundamental insights about how policy is made and implemented, and that some of the insights drawn from public choice theory are fundamentally flawed. Public choice, like many other research agendas, is a collection of imperfect attempts to understand complex and dynamic phenomena. One reason for this imperfection is that unlike in physics where the particles rarely learn from the researchers, those who make or implement policy – or at least want to bend policy for their own purposes – have often used public choice as a way of justifying those purposes.