Lewis was born in New York City on March 27, 1927. He attended the Horace Mann School in New York and received his BA degree from Harvard College in 1948. Lewis won his first Pulitzer Prize for national reporting in 1955 as a reporter for the Washington Daily News before joining The New York Times in 1955. After joining the The Times, he won a second Pulitzer Prize in 1963 for his coverage of the US Supreme Court.
Lewis has written three books: Gideon's Trumpet, about a landmark Supreme Court case that compelled states to provide attorneys for indigent defendants; Portrait of a Decade, about the seismic changes in American race relations; and Make No Law, about Times v. Sullivan, a Supreme Court case that changed the course of First Amendment litigation in America.
For 15 years, Lewis taught a course on the Constitution and the press at Harvard Law School. Last year, he was named Visiting Lombard Lecturer at Harvard's Kennedy School of Government.