The Federal Judicial Center career line is short and official. Law clerk to Judge Dorothy W. Nelson, Ninth Circuit, 1994–1995. Trial attorney, Civil Rights Division, Department of Justice, 1995–1998. Assistant United States Attorney, District of Massachusetts, 1998–2004. Private practice, Washington, D.C., 2004–2007. Deputy chief investigative counsel, House Oversight, 2007–2009; chief investigative counsel, House Energy and Commerce, 2009. Then the Department of Homeland Security: associate general counsel, 2009–2011; deputy general counsel, 2011–2014.
The District of Maryland chambers biography adds education the FJC lists only as degrees: Harvard College B.A. 1991; Harvard Law J.D. 1994; the court page states magna cum laude at the law school and editor of the Harvard Law Review. The same page records two terms on the Lexington, Massachusetts, Town Meeting; Board of Governors of the D.C. Bar; membership in the American Law Institute; and later service on the Harvard Board of Overseers.
An Obama White House release dated September 25, 2013, announcing the nomination, matches the same DHS title: Deputy General Counsel of the United States Department of Homeland Security.
Those are documented roles. They are not a finding that every later immigration or DHS-adjacent case required recusal. Recusal arguments live in a separate post, labeled as commentary.