Kroupa received a Bachelor of Science in Foreign Service from the Georgetown University Edmund A. Walsh School of Foreign Service in 1978, followed in 1981 by a Juris Doctor from the University of South Dakota School of Law. Prior to appointment to the Tax Court, Kroupa worked for the Internal Revenue Service as attorney-advisor, Legislation and Regulations Division, Office of Chief Counsel. She also worked at the Tax Court prior to her appointment as an attorney-advisor to Judge Joel Gerber from 1984-1985. Kroupa also practiced tax law at Faegre & Benson, LLP in Minneapolis, was a Minnesota Tax Court Judge from 1995 to 2001 and Chief Judge from 1998 to 2001. She was appointed by President George W. Bush as Judge, United States Tax Court, on June 13, 2003, for a term ending June 12, 2018. She retired from the Tax Court on June 16, 2014.