Mike Day

Michael B. Day


Michael B. Day represents clients in a wide range of regulated industries before California regulatory agencies, with an emphasis on cases before the California Public Utilities Commission (CPUC).


  • Cornell University (B.A. 1973)
  • University of California, Hastings College of the Law (J.D. 1976)


  • U.S. Supreme Court
  • U.S. Court of Appeals, District of Columbia
  • U.S. Court of Appeals, Fifth Circuit

professional activities

  • President of the Conference of California Public Utility Counsel, 1999-2000



  • Recognized in the 27th Edition of Best Lawyers in America for 2021 in the category of Energy Law
  • 2019 Lawyer of the Year in the 25th Edition of Best Lawyers in America in the category of Energy Law in the San Francisco Bay Area
  • Michael Day has been continuously selected for recognition in Best Lawyers in America from 1995 to 2020

Mr. Day’s practice includes natural gas and electric ratemaking proceedings, natural gas and electric transmission siting cases, and wireless telecommunications cases. Much of his practice focuses on the creation of competitive telecommunications and energy markets in California, primarily through advocacy before the CPUC, the California Energy Commission, and the California Independent System Operator, as well as through legislation under consideration by the California Legislature.

A Focus on Energy Regulation
Since 1991, Mr. Day has been the lead California regulatory counsel for a number of major energy companies, including pipelines, transmission line developers, and gas and electric marketers. As counsel to Wild Goose Storage, he obtained CPUC authorization for the first independent gas storage utility in California. He also serves a California regulatory counsel for PacifiCorp, a subsidiary of Berkshire Hathaway Energy.

His practice also emphasizes the development of new energy infrastructure in California. He served as California regulatory counsel for the innovative Path 15 Upgrade Project, the first independently financed transmission project in the United States. He represented the Trans Bay Cable Project, which constructed an underwater DC power line under San Francisco Bay.  Mr. Day successfully represented the City of Chino Hills in requiring the construction of the first underground 500kV transmission line to be built in the United States to mitigate the impact of a major transmission line planned for a narrow right of way through the city.

Other Regulatory Experience
Mr. Day also serves as California regulatory counsel for CTIA – The Wireless Association®, the national trade association of major wireless carriers.  He was lead counsel in the wireless industry’s successful efforts to preserve federal pre-emption of state rate authority over cellular services and to develop consumer protection rules suited to the competitive wireless market.  Mr. Day represented the City of San Clemente in obtaining approval for multiple pedestrian and highway grade crossings to facilitate the innovative San Clemente Beach Trail which ensured safety for both rail operations and pedestrian beach access.

Mr. Day frequently provides regulatory advice to investors and project sponsors who seek to develop energy projects in California.  He also provides California regulatory representation for the Solar Energy Industry Association, a national trade association of solar photovoltaic manufacturers, and is active in a wide range of renewable energy policy issues in California.

Previous Professional Experience
Mr. Day joined Goodin MacBride in January 1998, from the firm of Wright & Talisman, whose San Francisco office he had opened as a partner in 1991. From 1980-1991, he held several positions in the Legal Division at the CPUC, including lead counsel in natural gas matters before the Federal Energy Regulatory Commission; Deputy General Counsel supervising all appellate and advisory matters before the commission; and Acting General Counsel to the CPUC.  Prior to that, he was a trial attorney with Thornton, Taylor & Downs in San Francisco, specializing in property insurance litigation.