Marin began her journalism career in 1972 at WBIR-TV in Knoxville, Tennessee working as a reporter, anchor, and assistant news director.
In 1976, she moved to WSM-TV in Nashville, where she was instrumental in the investigative reporting that ultimately led to the ouster and indictment of then-Tennessee Governor Ray Blanton.
In a dual assignment, she worked as a network correspondent and an investigative reporter for WBBM-TV, the CBS station in Chicago.
Most recently, she and Chicago Sun-Times colleagues Tim Novak and Chris Fusco received the 2014 George Polk Award in Journalism for their reporting on The Killing of David Koschman.
She is married to World War II historian and author Jonathan Utley, Professor emeritus of the University of Tennessee.