Professor Hempling is an attorney, expert witness and teacher focusing on excellence in public utility regulation.

As an attorney, he has assisted clients from all industry sectors—regulators, utilities, consumer organizations, independent competitors and environmental organizations. As an expert witness, he has testified numerous times before state commissions and before committees of the United States Congress and the legislatures of Arkansas, California, Maryland, Minnesota, Nevada, North Carolina, South Carolina, Vermont, and Virginia. As a teacher and seminar presenter, he has taught public utility law and policy to a generation of regulators and practitioners, appearing throughout the United States, Australia, Belgium, Canada, Central America, England, Germany, India, Italy, Jamaica, Mexico, New Zealand, Norway, Peru, and Nigeria.

The first volume of his legal treatise, Regulating Public Utility Performance: The Law of Market Structure, Pricing and Jurisdiction, was published by the American Bar Association in 2013. His book Regulating Mergers and Acquisitions of U.S. Electric Utilities: Industry Concentration and Corporate Complication was published by Edward Elgar in Fall 2020. He also has authored a book of essays, Preside or Lead? The Attributes and Actions of Effective Regulators (2013). The essays continue monthly at

His articles have appeared in The Electricity Journal, Public Utilities Fortnightly,, publications of the American Bar Association, and other professional publications, covering such topics as mergers and acquisitions, the introduction of competition into formerly monopolistic markets, corporate restructuring, ratemaking, utility investments in nonutility businesses, transmission planning, renewable energy and state–federal jurisdictional issues. From 2006 to 2011, he was the Executive Director of the National Regulatory Research Institute.

Professor Hempling received a B.A. cum laude in (1) Economics and Political Science and (2) Music from Yale University, where he was a recipient of a Continental Grain Fellowship and a Patterson research grant. He received a J.D. magna cum laude from Georgetown University Law Center, where he was the recipient of an American Jurisprudence award for Constitutional Law.