State Secrets Privilege

The state secrets privilege is an evidentiary rule created by United States legal precedent. Application of the privilege results in exclusion of evidence from a legal case based solely on affidavits submitted by the government stating that court proceedings might disclose sensitive information which might endanger national security.United States v. Reynolds, which involved military secrets, was the first case that saw formal recognition of the privilege.

Following a claim of "state secrets privilege", the court rarely conducts an in camera examination of the evidence to evaluate whether there is sufficient cause to support the use of this doctrine. This results in court rulings in which even the judge has not verified the veracity of the assertion. The privileged material is completely removed from the litigation, and the court must determine how the unavailability of the privileged information affects the case.

The purpose of the state secrets privilege is to prevent courts from revealing state secrets in the course of civil litigation (in criminal cases, the Classified Information Procedures Act serves the same purpose). The government may intervene in any civil suit, including when it is not a party to the litigation, to ask the court to exclude state secrets evidence. While the courts may examine such evidence closely, in practice they generally defer to the Executive Branch. Once the court has agreed that evidence is subject to the state secrets privilege, it is excluded from the litigation. Often, as a practical matter, the plaintiff cannot continue the suit without the privileged information, and drops the case. Recently, courts have been more inclined to dismiss cases outright, if the subject matter of the case is a state secret.

The state secrets privilege is related to, but distinct from, several other legal doctrines: the principle of non-justiciability in certain cases involving state secrets (the so-called "Totten Rule"); certain prohibitions on the publication of classified information (as in New York Times Co. v. United States, the Pentagon Papers case); and the use of classified information in criminal cases (governed by the Classified Information Procedures Act).

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