[6][7] Harris is known to be a strong opponent of the worldwide mass surveillance activities of the U.S. National Security Agency (NSA).

[8] In 2010, Harris received the 24th annual Gerald R. Ford Prize for "Distinguished Reporting on National Defense".

[9] In 2019, Harris and others at the Washington Post were finalists for the Pulitzer Prize for Public Service for their coverage of the assassination of Jamal Khashoggi by Saudi Arabia's Crown Prince Mohammed bin Salman.

[10] Harris is the author of The Watchers: The Rise of America's Surveillance State, which won the Helen Bernstein Book Award for Excellence in Journalism in 2011.

[12] He is also the author of @War: The Rise of the Military-Internet Complex, which Lawfare described as superb, noting that, "Few books on a subject as technical as network security can be fairly described as riveting, but Harris has managed to pull off a rare feat: a story that is simultaneously rigorous, comprehensive, and a joy to read".