Law and economics is an interdisciplinary field that examines how economic theory can inform and shape legal rules. Specifically, microeconomic theory is used to analyze legal rules and institutions.
A great introduction to the field is Chicago Lectures in Law and Economics by Eric Posner (Foundation Press, 2000) (available in HeinOnline). The book is a collection of essays based on lectures presented at the University of Chicago Law School that were designed to introduce law students, especially first year law students, to the economic analysis of law.
Another great resource is Jeffrey L. Harrison, Law and Economics in a Nutshell (7th ed.) (West Academic, 2020) (available online here).
The University of Chicago Law School is considered to be the birthplace of the law and economics movement, as evident by the early inclusion of economics scholars (including Milton Friedman and George Stigler) onto the law school faculty and the founding of the Journal of Law and Economics. If you are interested in the history of law and economics at the Law School, please read the special issue of the Law School Record from Fall 2011, available on Chicago Unbound, the institutional repository for the Law School. This issue also has an article about the creation of the Coase-Sandor Institute for Law and Economics and features interviews with ten University of Chicago Law School faculty about the future of law and economics.
The Coase-Sandor Institute for Law and Economics at the Law School is one of the significant avenues by which the Law School supports and contributes to the study of law and economics. The Coase-Sandor Institute aims to promote the understanding and dissemination of the economic approach to law. As part of this mission, the Institute supports the research of Law School faculty in this area.
The Institute hosts the annual Coase lecture series, where University of Chicago Law School faculty present scholarship related to the economic analysis of the law. This lecture series, established in 1992 to honor the late Ronald Coase, highlights the Law School's tradition of deep scholarship in this area. You can see a recording of the most recent lecture below, and recordings of earlier Coase lectures on Chicago Unbound. If you are interested in learning more about the activities of the institute, you can access their annual reports on Chicago Unbound.