Recognized in Ones to Watch since 2022 
Peter E. Madsen is an attorney with Keegan Werlin LLP in Lexington, Massachusetts. His practice focuses on Administrative / Regulatory Law and Energy Law, with experience representing public utilities and energy companies in a range of state regulatory proceedings and compliance matters.
Before joining Keegan Werlin LLP in 2024, Mr. Madsen practiced in the energy group of a national law firm, where he advised clients on regulatory and administrative matters before state public utilities commissions. His work included utility ratemaking proceedings, permitting and siting matters for large energy facilities, regulatory compliance issues, contested case proceedings, and related appeals.
Prior to entering private practice, Mr. Madsen served as an Assistant Attorney General with the Minnesota Attorney General’s Office. In that role, he represented a state agency in energy and public utility regulatory proceedings before the Minnesota Public Utilities Commission. His experience included general rate cases, certificate of need proceedings, and matters involving major energy infrastructure projects, including transmission lines and crude oil pipelines.
