Thomas Oliphant was born in Brooklyn, New York. He graduated in 1967 from Harvard University.
In 1968 he joined the Boston Globe. During his career with the newspaper, he served as its Washington correspondent and reported on 10 Presidential campaigns. He was one of three editors who managed The Globe's coverage of school desegregation in Boston, work which won a 1975 Pulitzer Prize. He also received a writing award from the American Society of Newspaper Editors.
In March 2005, Oliphant suffered a brain aneurysm. His account of the experience and his recovery appeared in The Globe on June 5, 2005. At the end of 2005, he was one of 32 Globe staff members who accepted a retirement buyout package from the New York Times Company, owner of The Globe.
Oliphant has been a frequent guest on television news programs, including "Nightline" on ABC-TV, "The NewsHour" with Jim Lehrer on PBS, "Face The Nation," the "Today" show, "Good Morning America" and "CBS This Morning." His last appearance on Jim Lehrer's program was on Wednesday, August 26, 2009, when he discussed the legacy of Ted Kennedy. Oliphant was also a regular guest on "The Al Franken Show," where he also appeared as a guest host in August 2006.
Oliphant is married to CBS reporter Susan Spencer.