A native of Waco, Texas, she earned an undergraduate degree in political science from Vassar College in 1965 and a J.D. with honors from The George Washington University Law School in 1968. She married lawyer John L. Richardson in 1967 and has one daughter. She is a member of the District of Columbia and Virginia bars and is a Fellow of the American Bar Foundation.
Richardson clerked at the U.S. Court of Claims before joining the Office of Chief Counsel of the IRS, eventually becoming the first woman promoted to executive rank in that office's history.
In 1977, Richardson joined law firm Sutherland, Asbill and Brennan in Washington D.C., becoming a partner in 1980 until her 1993 IRS appointment. During her tenure, she was appointed to the IRS Commissioner's Advisory Group, serving as a member from 1988 to 1990 and as chair from 1989 to 1990.
Following her service as IRS Commissioner, Richardson became a member of Ernst & Young, in Washington, D.C. from December 1997 to 2003. She has since served on the boards of Jackson Hewitt Tax Service, Inc. and Legg Mason.