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The Fourth Amendment's National Security Exception: Its History and Limits
Vanderbilt Law Review (2013)
  • L. Rush Atkinson
Each year, federal agents conduct thousands of “national security investigations” into suspected spies, terrorists, and other foreign threats. The constitutional limits imposed by the Fourth Amendment, however, remain murky, and the extent to which national security justifies deviations from the Amendment’s traditional rules is unclear. With little judicial precedent on point, the gloss of past executive practice has become an important means for gauging the boundaries of today’s national security practices. Accounts of past executive practice, however, have thus far been historically incomplete, leading to distorted analyses of its precedential significance. Dating back to World War II, national security investigations have involved warrantless surveillance and searches—conduct clearly impermissible in the traditional law-enforcement context—authorized under the theory of a “national security” or “foreign intelligence” exception to the Fourth Amendment. Out of a sense of constitutional obligation, however, those who crafted this exception also circumscribed it. Information derived from warrantless searches was treated as inadmissible in subsequent trials, a caveat that tempered the exception but also inhibited the conviction of spies and other foreign agents. For decades, this “purely intelligence” restriction, as FBI Director J. Edgar Hoover called it, served as the constitutional boundary for agents working on national security matters. The FBI’s “pure intelligence” precedent provides a useful lens for studying the modern surveillance programs now subject to constitutional litigation. As recently noted by the Supreme Court in Clapper v. Amnesty International USA, it appears that no information gathered by recent warrantless surveillance has been used in criminal prosecutions. This adherence—conscious or inadvertent—to a new, de facto pure -intelligence rule has mimicked the historical constraints placed on national security investigations. Such parallelism bolsters claims that certain surveillance programs can pass constitutional muster under the Fourth Amendment’s national security exception without posing a threat to the traditional safeguards of our civil liberties.
  • National Security,
  • Fourth Amendment,
  • Foreign Intelligence Surveillance Act,
  • FISA Amendments Act
Publication Date
Citation Information
L. Rush Atkinson. "The Fourth Amendment's National Security Exception: Its History and Limits" Vanderbilt Law Review Vol. 66 Iss. 5 (2013)
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