The state secrets privilege, primarily a construct of the judiciary that has been derived from common law, is an evidentiary privilege that allows the government to resist court-ordered disclosure of information during civil litigation if there is a reasonable danger that such disclosure would harm the national security of the United States. The privilege belongs to the government alone, and may be invoked only after personal consideration by the head of the department with control over the information. The validity of the claim is then independently evaluated by the court after an inquiry that may require in camera review of the information sought to be protected. If the court determines that the information in question falls under the protection of the state secrets privilege, then the information will be considered unavailable, and the court must determine how or whether the litigation can proceed absent the protected evidence. In recent years, some have suggested that the privilege has been overused by the executive branch to prevent disclosure of its own questionable, embarrassing, or unlawful conduct—particularly with respect to the "war on terror." In response, the Obama Administration has issued a new policy on the state secrets privilege in an attempt to "strengthen public confidence that the U.S. government will invoke the privilege in court only when genuine and significant harm to national defense or foreign relations is at stake and only to the extent necessary to safeguard those interests." Under the policy established by Attorney General Eric Holder, any decision by an agency to invoke the privilege in litigation must first be reviewed by a State Secrets Review Committee and receive the personal approval of the Attorney General. The new procedures specifically state that the Department of Justice will not defend an invocation of the state secrets privilege to conceal "violations of the law" or "administrative error"; avoid "embarrassment"; or to "prevent or delay the release of information … which would not reasonably be expected to cause significant harm to national security ." While the state secrets privilege arises in a wide array of cases, recently the privilege has been characterized by a number of high-profile assertions—including invocation of the privilege to defend against claims arising from the government's "extraordinary rendition" practices, challenges to the terrorist surveillance program, and claims against various national security agencies for unlawful employment practices. The government has also intervened and invoked the privilege in a significant number of cases involving claims against government contractors. This report is intended to present an overview of the protections afforded by the state secrets privilege; a discussion of some of the many unresolved issues associated with the privilege; and, a selection of high-profile examples of how the privilege has been applied in practice. Although previously established, the Supreme Court first articulated the modern analytical framework of the state secrets privilege in the 1953 case of United States v. Reynolds . That case involved multiple wrongful death claims brought by the widows of three civilians who died aboard a military aircraft that crashed while testing secret electronic equipment. The plaintiffs had sought discovery of the official post-incident report and survivors' statements that were in the possession of the U.S. Air Force. The Air Force opposed disclosure of those documents, as the aircraft and its occupants were engaged in a "highly secret mission of the Air Force" at the time of the crash. The federal district court ordered the Air Force to produce the documents so that it could independently determine whether they contained privileged information. When the Air Force refused to provide the documents to the court, the district court ruled in favor of the plaintiffs on the issue of negligence; the court of appeals subsequently affirmed the district court's ruling. The Supreme Court reversed. In its opinion, the Court laid out a two-step procedure to be used when evaluating a claim of privilege to protect state secrets. First, "there must be a formal claim of privilege, lodged by the head of the department which has control over the matter, after actual personal consideration by that officer." Second, "the court itself must determine whether the circumstances are appropriate for the claim of privilege, and yet do so without forcing a disclosure of the very thing the privilege is designed to protect." Ultimately, the Reynolds Court determined that the Air Force's invocation of the privilege was valid and that in camera review of the incident report was not necessary. Importantly, the Court did not dismiss the claims, but rather remanded the case and directed the district court to provide the plaintiffs with the opportunity to pursue their case without the privileged evidence. The first requirement identified by the Reynolds Court, the assertion of the privilege, is a largely procedural hurdle to assure that the privilege is not "lightly invoked." Nevertheless, this requirement is readily met through the written assertion of the privilege by the head of the department in control of the information in question after "personal consideration." Furthermore, the privilege belongs exclusively to the government and therefore cannot be validly asserted by a private party. In cases in which the government is not a party, but the nature of the claim is such that litigation could potentially lead to the disclosure of secret evidence that would threaten national security, the government must itself intervene and assert the state secrets privilege. It should be noted, however, that the government's failure to formally assert the privilege has previously been excused because strict adherence to the requirement would have had little or no benefit. Finally, most courts have determined that the privilege may be raised at any time. For instance, the privilege may be raised prospectively at the pleading stage of the litigation, or during discovery in response to specific requests for information. In contrast to the requirement that the government formally assert the privilege, the requirement that the court evaluate the validity of the government's claim often "presents real difficulty." Accordingly, the government "bears the burden of satisfying a reviewing court that the Reynolds reasonable-danger standard is met." For example, although the Supreme Court's holding in Reynolds recognized that it is the role of the judiciary to evaluate the validity of a claim of privilege, the Court declined to require that courts automatically compel inspection of the underlying information. As the Court noted, "too much judicial inquiry into the claim of privilege would force disclosure of the thing the privilege was meant to protect, while a complete abandonment of judicial control would lead to intolerable abuses." Therefore, although the privilege requires some deference to the executive branch, an independent evaluation of the claim of privilege is necessary so as not to abdicate control over evidence "to the caprice of executive officers." In light of this dilemma, the Court chose to chart a middle course, employing a "formula of compromise" to balance the competing interests of oversight by the judiciary, the plaintiffs' need for the evidence, and national security interests. Under this scheme, the privilege should be found valid when a court is satisfied that there is a reasonable danger that disclosure "will expose military matters which, in the interest of national security, should not be divulged." The thoroughness of a court's review of the government's assertion of the state secrets privilege varies. Generally, the depth of the inquiry corresponds to an evaluation of the opposing party's need for the information and the government's need to prevent disclosure. As part of this balancing, a court may go so far as to require the production of the evidence in question for in camera review. Under other circumstances, however, the nature of the evidence may be such that the court is satisfied that the evidence warrants protection based solely on the executive branch's assertions. No matter the depth of the inquiry, once a court is satisfied that the privilege is valid, it should not further "jeopardize the security which the privilege is meant to protect by insisting upon an examination of the evidence, even by the judge alone, in chambers." Whether a court may be satisfied without examining the underlying information will also be influenced by the amount of deference afforded to the government's representations regarding the evidence in question. In Reynolds , the Court noted that the necessity of the underlying information to the litigation will determine "how far the court should probe in satisfying itself that the occasion for invoking the privilege is appropriate." In the case of Reynolds , the Court noted that the Air Force had offered to make the surviving crew members available for examination by the plaintiffs. Because of this alternative avenue of information, the Court was satisfied that the privilege was valid based primarily upon representations made by the government regarding the contents of the documents. Conversely, less deference to the government's representations may be warranted where a private litigant has a strong need for the information. When possible, courts have attempted to "disentangle" privileged evidence from non-privileged evidence. One way to protect privileged information without excluding non-privileged evidence is to redact sensitive portions of a document rather than barring the entire piece of evidence. However, some courts have questioned the prudence of using redaction to protect portions of documents that qualify for protection under the privilege out of a concern that pieces of "seemingly innocuous" information can create a "mosaic" through which protected information may be deduced. The "mosaic theory" is based on the principle that federal judges are not properly equipped to determine which pieces of information, when taken together, could result in the disclosure "of the very thing the privilege is designed to protect." Adherence to the mosaic theory, however, necessarily results in broad deference to the assertions of intelligence agencies. If the privilege is appropriately invoked, it is absolute and the disclosure of the underlying information cannot be compelled by the court. Although a private litigant's need for the information may be relevant to the amount of deference afforded to the government, "even the most compelling necessity cannot overcome the claim of privilege if the court is ultimately satisfied" that the privilege is appropriate. Still, a valid invocation of the privilege does not necessarily require dismissal of the claim. In Reynolds , for instance, the Supreme Court did not dismiss the plaintiffs' claims, but rather remanded the case to determine whether the claims could proceed absent the privileged evidence. Yet, significant controversy has arisen with respect to the question of how a case should proceed in light of the successful claim of privilege.