Marilyn Thompson was born in Salisbury, NC in 1952. She was a 1974 graduate of Clemson University where she received a BA in English. Her initial aim was to become a teacher, but after working with the Clemson student newspaper The Tiger, she found journalism to be her calling.

After graduation she worked at the Columbia Record in Columbia, South Carolina as a governmental affairs and investigative reporter where she earned South Carolina Journalist of the Year honors. In 1982 she was named a Congressional Fellow by the American Political Science Association.

From 1982-1986 she worked as a general assignment reporter for the Philadelphia Daily News. In 1986 she moved to the New York Daily News as a general assignment reporter. In 1987 she was promoted to Assistant City Editor for Investigations before being transferred in 1988 to the Washington Bureau in order to cover the Justice Department. While there, she helped break a government corruption story that later would become the book Feeding the Beast: How Wedtech Became the Most Corrupt Little Company in America. Following this time period, she was for two years Executive Editor and VP of the Lexington Herald-Ledger in Lexington, Kentucky.

She joined the Washington Post in 1990, where she spent fourteen years as Metropolitan Projects Editor, National Desk as Deputy National Editor for Domestic Coverage, Investigations Editor, and Assistant Managing Editor of the Investigative Team (a group which twice won the Pulitzer Prize for Public Service). In the aftermath of the terrorist attacks on the United States in 2001, she wrote The Killer Strain: Anthrax and a Government Exposed.

In 2003, she helped break the story regarding Strom Thurmond’s mixed-race daughter Essie Mae Washington-Williams. This and other issues were brought to light in a book she co-wrote with author Jack Bass entitled Ol’ Strom: An Unauthorized Biography. In recent years she has worked with the Washington Bureaus of the New York Times and Los Angeles Times, has been involved with the Investigative Reporters & Editors group, the Fund for Investigative Journalism, and has been a Ferris Professor of the Humanities at Princeton University.