upon the sole ground that officers reasonably expected to find evidence of a particular crime and voluntarily confined their activities to the least intrusive means consistent with that end." Katz, supra, at 356-357. The Fourth Amendment contemplates a prior judicial judgment,18 not the risk that executive discretion may be reasonably exercised. This judicial role accords with our basic constitutional doctrine that individual freedoms will best be preserved through a separation of powers and division of functions among the different branches and levels of Government. John M. Harlan, Thoughts at a Dedication: Keeping the Judicial Function in Balance, 49 A.B.A.J. 943-944 (1963). The independent check upon executive discretion is not satisfied, as the Government argues, by "extremely limited" post-surveillance judicial review.19 Indeed, post-surveillance review would never reach the surveillances which failed to result in prosecutions. Prior review by a neutral and detached magistrate is the time tested means of effectuating Fourth Amendment rights. Beck v. Ohio, 379 U.S 89, 96 (1964).

It is true that there have been some exceptions to the warrant requirement. Chimel v. California, 395 U.S. 752 (1969); Terry v. Ohio, 392 U.S. 1 (1968); U.S. 132 (1925). But those exceptions are few in number and carefully delineated. Katz, supra, at 357; in general they serve the legitimate needs of law enforcement officers to protect their own well-being and preserve evidence from destruction. Even while carving out those exceptions, the Court has reaffirmed the principle that the "police must, whenever practicable, obtain advance judicial approval of searches and seizures through the warrant procedure," Terry v. Ohio, supra, at 20; Chimel v. California, supra, at 762.

The Government argues that the special circumstances applicable to domestic security surveillances necessitate a further exception to the warrant requirement. It is urged that the requirement of prior judicial review would obstruct the President in the discharge of his constitutional duty to protect domestic security. We are told further that these surveillances are directed primarily to the collecting and maintaining of intelligence with respect to subversive forces, and are not an attempt to gather evidence for specific criminal prosecutions. It is said that this type of surveillance should not be subject to traditional warrant requirements which were established to govern investigation of criminal activity, not on-going intelligence gathering. Govt. Brief, pp. 15-16, 23-24. Govt. Reply Brief, pp. 2-3.

The Government further insists that courts "as a practical matter would have neither the knowledge nor the techniques necessary to determine whether there was probable cause to believe that surveillance was necessary to protect national security." These security problems, the Government contends, involve "a large number of complex and subtle factors" beyond the competence of courts to evaluate. Govt. Reply Brief, p. 4.

As a final reason for exemption from a warrant requirement, the Government believes that disclosure to a magistrate of all or even a significant portion of the information involved in domestic security surveillances "would create serious potential dangers to the national security and to the lives of informants and agents. . . . Secrecy is the essential ingredient in intelligence gathering; requiring prior judicial authorization would create a greater 'danger of leaks. . ., because in addition to the judge, you have the clerk, the stenographer and some other official like a law assistant or bailiff who may be apprised of the nature' of the surveillance." Govt. Brief, pp. 24-25.

These contentions in behalf of a complete exemption from the warrant requirement, when urged on behalf of the President and the national security in its domestic implications, merit the most careful consideration. We certainly do not reject them lightly, especially at a time of worldwide ferment and when civil disorders in this country are more prevalent than in the less turbulent periods of our history. There is, no doubt, pragmatic force to the Government's position.

18 We use the word "judicial" to connote the traditional Fourth Amendment requirement of a neutral and detached magistrate.

19 The Government argues that domestic security wiretaps should be upheld by courts in post surveillance review "unless it appears that the Attorney General's determination that the proposed surveillance relates to a national security matter is arbitrary and capricious, i.e., that it constitutes a clear abuse of the broad discretion that the Attorney General has to obtain all information that will be helpful to the President in protecting the Government . . ." against the various unlawful acts in § 2511 (3). Govt. Brief, p. 22.

But we do not think a case has been made for the requested departure from Fourth Amendment standards. The circumstances described do not justify complete exemption of domestic security surveillance from prior judicial scrutiny. Official surveillance, whether its purpose be criminal investigation or on-going intelligence gathering, risks infringement of constitutionally protected privacy of speech. Security surveillances are especially sensitive because of the inherent vagueness of the domestic security concept, the necessarily broad and continuing nature of intelligence gathering, and the temptation to utilize such surveillances to oversee political dissent. We recognize, as we have before, the constitutional basis of the President's domestic security role, but we think it must be exercised in a manner compatible with the Fourth Amendment. In this case we hold that this requires an appropriate prior warrant procedure.

We cannot accept the Government's argument that internal security matters are too subtle and complex for judicial evaluation. Courts regularly deal with the most difficult issues of our society. There is no reason to believe that federal judges will be insensitive to or uncomprehending of the issues involved in domestic security cases. Certainly courts can recognize that domestic security surveillance involves different considerations from the surveillance of ordinary crime. If the threat is too subtle or complex for our senior law enforcement officers to convey its significance to a court, one may question whether there is probable cause for surveillance.

Nor do we believe prior judicial approval will fracture the secrecy essential to official intelligence gathering. The investigation of criminal activity has long involved imparting sensitive information to judicial officers who have respected the confidentialities involved. Judges may be counted upon to be especially conscious of security requirements in national security cases. Title III of the Omnibus Crime Control and Safe Streets Act already has imposed this responsibility on the judiciary in connection with such crimes as espionage, sabotage and treason, § 2516 (1) (a) (c), each of which may involve domestic as well as foreign security threats. Moreover, a warrant application involves no public or adversary proceedings: it is an ex parte request before a magistrate or judge. Whatever security dangers clerical and secretarial personnel may pose can be minimized by proper administrative measures, possibly to the point of allowing the Government itself to provide the necessary clerical assistance.

Thus, we conclude that the Government's concerns do not justify departure in this case from the customary Fourth Amendment requirement of judicial approval prior to initiation of a search or surveillance. Although some added burden will be imposed upon the Attorney General, this inconvencience is justified in a free society to protect constitutional values. Nor do we think the Government's domestic surveillance powers will be impaired to any significant degree. A prior warrant establishes presumptive validity of the surveillance and will minimize the burden of justification in post-surveillance judicial review. By no means of least importance will be the reassurance of the public generally that indiscriminate wiretapping and bugging of law-abiding citizens cannot occur.

IV

We emphasize, before concluding this opinion, the scope of our decision. As stated at the outset, this case involves only the domestic aspects of national security. We have not addressed, and express no opinion as to, the issues which may be involved with respect to activities of foreign powers or their agents.20 Nor does our decision rest on the language of § 2511 (3) or any other section of Title III of the Omnibus Crime Control and Safe Streets Act of 1968. That Act does not attempt to define or delineate the powers of the President to meet domestic threats to the national security.

Moreover, we do not hold that the same type of standards and procedures prescribed by Title III are necessarily applicable to this case. We recognize that domestic security surveillance may involve different policy and practical considerations from the surveillance of "ordinary crime." The gathering of

20 See n. 8, supra. For the view that warrantless surveillance, though impermissible in domestic security cases, may be constitutional where foreign powers are involved, see United States v. Smith, F. Supp. (1971); and American Bar Association Criminal Justice Project, Standards Relating to Electronic Surveillance, Feb. 1971, pp. 11, 120, 121. See also United States v. Clay, 430 F.2d 165 (1970).

93-045-73--14

security intelligence is often long range and involves the interrelation of various sources and types of information. The exact targets of such surveillance may be more difficult to identify than in surveillance operations against many types of crime specified in Title III. Often, too, the emphasis of domestic intelligence gathering is on the prevention of unlawful activity or the enhancement of the Government's preparedness for some possible future crisis or emergency. Thus, the focus of domestic surveillance may be less precise than that directed against more conventional types of crime.

Given these potential distinctions between Title III criminal surveillances and those involving the domestic security, Congress may wish to consider protective standards for the latter which differ from those already prescribed for specified crimes in Title III. Different standards may be compatible with the Fourth Amendment if they are reasonable both in relation to the legitimate need of Government for intelligence information and the protected rights of our citiznes. For the warrant application may vary according to the governmental interest to be enforced and the nature of citizen rights deserving protection. As the Court said in Camara v. Municiapl Court, 387 U.S. 523, 534-535 (1967):

"In cases in which the Fourth Amendment requires that a warrant to search be obtained, 'probable cause' is the standard by which a particular decision to search is tested against the constitutional mandate of reasonableness. In determining whether a particular inspection is reasonable -and thus in determining whether there is probable cause to issue a warrant for that inspection-the need for the inspection must be weighed in terms of these reasonable goals of law enforcement."

It may be that Congress, for example, would judge that the application and affidavit showing probable cause need not follow the exact requirements of § 2518 but should allege other circumstances more appropriate to domestic security cases; that the request for prior court authorization could, in sensitive cases, be made to any member of a specially designated court (e.g., the District Court or Court of Appeals for the Disrict of Columbia); and that the time and reporting requirements need not be so strict as those in §2518.

The above paragraph does not, of course, attempt to guide the congressional judgment but rather to delineate the present scope of our own opinion. We do not attempt to detail the precise standards for domestic security warrants any more than our decision in Katz sought to set the refined requirements for the specified criminal surveillances which now constitute Title III. We do hold, however, that prior judicial approval is required for the type of domestic security surveillance involved in this case and that such approval may be made in accordance with such reasonable standards as the Congress may prescribe.

V

As the surveillance of Plamondon's conversations was unlawful, because conducted without prior judicial approval, the courts below correctly held that Alderman v. United States, 394 U.S. 168 (1969), is controlling and that it requires disclosure to the accused of his own impermissibly intercepted conversations. As stated in Alderman, "the trial court can and should, where appropriate, place a defendant and his counsel under enforceable orders against unwarranted disclosure of the materials which they may be entitled to inspect." 394 U.S. 185.21

The judgment of the Court of Appeals is hereby

THE CHIEF JUSTICE Concurs in the result.

Affirmed.

MR. JUSTICE REHNQUIST took no part in the consideration or decision of this

case.

21 We think it unnecessary at this time and on the facts of this case to consider the arguments advanced by the Government for a re-examination of the basis and scope of the Court's decision in Alderman.

SUPREME COURT OF THE UNITED STATES

[No. 70-153]

UNITED STATES, PETITIONER, v. UNITED STATES DISTRICT COURT FOR THE EASTERN DISTRICT OF MICHIGAN, SOUTHERN DIVISION, ET AL.

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR THE
SIXTH CIRCUIT

MR. JUSTICE WHITE, Concurring in the judgment.

JUNE 19, 1972.

This case arises out of a two-count indictment charging conspiracy to injure and injury to Government property. Count I charged Robert Plamondon and two codefendants with conspiring with a fourth person to injure Government property with dynamite. Count II charged Plamondon alone with dynamiting and injuring Government property in Ann Arbor, Michigan. The defendants moved to compel the United States to disclose, among other things, any logs and records of electronic surveillance directed at them, at unindicted coconspirators, or at any premises of the defendants or coconspirators. They also moved for a hearing to determine whether any electronic surveillance disclosed had tainted the evidence on which the grand jury indictment was based and which the Government intended to use at trial. They asked for dismissal of the indictment if such taint were determined to exist. Opposing the motion, the United States submitted an affidavit of the Attorney General of the United States disclosing that "[t]he defendant Plamondon had participated in conversations which were overheard by Government agents who were monitoring wiretaps which were being employed to gather intelligence information deemed necessary to protect the Nation from attempts of domestic organizations to attack and subvert the existing structure of the Government," the wiretaps having been expressly approved by the Attorney General. The records of the intercepted conversations and copies of the memorandum reflecting the Attorney General's approval were submitted under seal and solely for the Court's in camera inspection.1

As characterized by the District Court, the position of the United States was that the electronic monitoring of Plamondon's conversations without judicial warrant was a lawful exercise of the power of the President to safeguard the national security. The District Court granted the motion of defendants, holding that the President had no constitutional power to employ electronic surveillance without warrant to gather information about domestic organizations. Absent probable cause and judicial authorization, the challenged wiretap infringed Plamondon's Fourth Amendment rights. The court ordered the Government to disclose to defendants the records of the monitored conversations and directed that a hearing be held to determine the existence of taint either in the indictment or in the evidence to be introduced at trial.

The Government's petition for mandamus to require the District Court to vacate its order was denied by the Court of Appeals. 444 F. 2d 651 (1971). That court held that the Fourth Amendment barred warrantless electronic surveillance of domestic organizations even if at the direction of the President. It agreed with the District Court that because the wiretaps involved were therefore constitutionally inform, the United States must turn over to defendants the records of overheard conversations for the purpose of determining whether the Government's evidence was tainted.

1 The Attorney General's affidavit concluded:

"I certify that it would prejudice the national interest to disclose the particular facts concerning these surveillances other than to the court in camera. Accordingly, the sealed exhibit referred to herein is being submitted solely for the court's in camera Inspection and a copy of the sealed exhibit is not being furnished to the defendants. I would request the court, at the conclusion of its hearing on this matter, to place the scaled exhibit in a sealed envelope and return it to the Department of Justice where it will be retained under seal so that it may be submitted to any appellate court that may review this matter." App. 20-21.

I would affirm the Court of Appeals but on the statutory ground urged by respondent Keith (Brief, p. 115) without reaching or intimating any views with respect to the constitutional issue decided by both the District Court and the Court of Appeals.

Title III of the Omnibus Crime Control and Safe Streets Act of 1968, 82 Stat. 212, 18 U.S.C. §§ 2510-2520, forbids under pain of criminal penalties and civil actions for damages any wiretapping or eavesdropping not undertaken in accordance with specified procedures for obtaining judicial warrants authorizing the surveillance. Section 2511 (1) establishes a general prohibition against electronic eavesdropping "except as otherwise specifically provided" in the statute. Later sections provide detailed procedures for judicial authorization of official interceptions of oral comunications; when these procedures are followed the interception is not subject to the prohibitions of § 2511(1). Section 2511(2), however, specifies other situations in which the general prohibitions of § 2511 (1) do not apply. In addition, § 2511 (3) provides that

"Nothing contained in this chapter or in section 605 of the Communications Act of 1934 (48 Stat. 1103; 47 U.S.C. § 605) shall limit the constitutional power of the President to take such measures as he deems necessary to protect the Nation against actual or potential attack or other hostile acts of a foreign power, to obtain foreign intelligence information deemed essential to the security of the United States, or to protect national security information against foreign intelligence activities. Nor shall anything contained in this chapter be deemd to limit the constitutional power of the President to take such measures as he deems necessary to protect the United States against the overthrow of the Government by force or other unlawful means, or against any other clear and present danger to the structure or existence of the Government. The contents of any wire or oral communication intercepted by authority of the President in the exercise of the foregoing powers may be received in evidence in any trial hearing, or other proceeding only where such interception was reasonable, and shall not be otherwise used or disclosed except as is necessary to implement that power."

It is this subsection that lies at the heart of this case.

The interception here was without judicial warrant, it was not covered by the provisions of § 2511 (2) and it is too clear for argument that it is illegal under § 2511 (1) unless it is saved by § 2511(3). The majority asserts that § 2511 (3) is a "disclaimer" but not an "exception." But however it is labeled, it is apparent from the face of the section and its legislative history that if this interception is one of those described in § 2511 (3), it is not reached by the statutory ban on unwarranted electronic eavesdropping.2

The defendants in the District Court moved for the production of the logs of any electronic surveillance to which they might have been subjected. The Government responded that conversations of Plamondon had been intercepted but took the position that turnover of surveillance records was not necessary because the interception complied with the law. Clearly, for the Government to prevail it was necessary to demonstrate first that the interception involved was not subject to the statutory requirement of judicial approval for wiretapping because the surveillance was within the scope of § 2511(3); and, secondly, if the Act did not forbid the warrantless wiretap, that the surveillance was consistent with the Fourth Amendment.

2 I cannot agree with the majority's analysis of the import of § 2511(3). Surely, Congress meant at least that if a court determined that in the specified circumstances the President could constitutionally intercept communications without a warrant, the general ban of § 2511(1) would not apply. But the limitation on the applicability of 2511(1) was not open-ended; it was confined to those situations which § 2511 (3) specifically described. Thus, even assuming the constitutionality of a warrantless surveil lance authorized by the President to uncover private or official graft forbidden by federal statute, the interception would be illegal under § 2511(1) because it is not the type of presidential action saved by the Act by the provision of § 2511(3). As stated in the text and footnote 3, the United States does not claim that Congress is powerless to require warrants for surveillances which the President otherwise would not be barred by the Fourth Amendment from undertaking without a warrant.