Sam Callahan

Sam Callahan, former Senior Counsel of the Office of Management and Budget (OMB), focuses on appellate and complex civil litigation with an emphasis on administrative law and regulatory matters. Sam has argued federal appeals and briefed dozens of cases across federal and state courts, winning major cases involving the Administrative Procedure Act (APA), constitutional and statutory interpretation, antitrust, insurance, voting rights, and maritime law. Sam also provides strategic counsel to businesses navigating high-stakes regulatory frameworks and government investigations.

At OMB, Sam supervised major litigation, reviewed regulations, managed legal and policy clearance of executive orders, and advised senior officials across the Biden Administration on key issues of administrative law, fiscal law, government contracts, and congressional oversight. As a principal legal advisor to OMB's Office of Information and Regulatory Affairs (OIRA) and Office of Federal Procurement Policy (OFPP), Sam developed extensive experience with the APA and with federal contracting and funding laws, including the Federal Property and Administrative Services Act, Federal Acquisition Regulation, and Uniform Grants Guidance. His portfolio spanned technology, healthcare, environmental, procurement, and budgetary policies, including leading review of landmark federal AI regulations.

Sam clerked for Judge Paul V. Niemeyer of the U.S. Court of Appeals for the Fourth Circuit and Judge Christopher R. Cooper of the U.S. District Court for the District of Columbia. He graduated magna cum laude from Harvard Law School, where he was an Executive Editor of the Harvard Law Review, and received degrees in economics and trumpet performance from Indiana University. He remains active in music as a member of the Capital City Symphony and as a National Endowment for the Arts grants panelist.