POSNER, Circuit Judge.
This appeal by the United States raises two novel and important questions: whether the federal government may ever secretly televise the interior of a private building as part of a criminal investigation and use the videotapes in a criminal trial, and if so whether the warrants under which television surveillance was conducted in this case complied with constitutional requirements. A federal grand jury indicted the four defendants, who are members of the FALN (Fuerzas Armadas de Liberación Nacional Puertorriqueña), on charges of seditious conspiracy (18 U.S.C. § 2384) and related weapons and explosives violations. On the eve of trial, the district judge ordered the suppression of videotapes that the FBI had made as part of its surveillance of two FALN safe houses. 583 F.Supp. 86, 99-105 (N.D.Ill.1984). The government appeals this order under 18 U.S.C. § 3731. The videotapes had no sound track; but at the same time that the FBI was televising the interior of the safe houses it was recording the sounds on different equipment. The judge refused to order suppression of the sound tapes, and they are not in issue in this appeal.
The FALN is a secret organization of Puerto Rican separatists that has been trying to win independence for Puerto Rico by tactics that include bombing buildings in New York, Chicago, and Washington. The bombs are assembled and stored, and members of the organization meet, in safe houses rented under false names. The bombings have killed several people, injured many others, and caused millions of dollars [877]*877of property damage. See 583 F.Supp. at 91; In re Special February 1975 Grand Jury, 565 F.2d 407, 409-10 (7th Cir.1977); United States v. Rosado, 728 F.2d 89, 91-92 (2d Cir.1984); In re Archuleta, 561 F.2d 1059, 1060 (2d Cir.1977); In re Cueto, 443 F.Supp. 857, 858 (S.D.N.Y.1978); Breasted, 3-Year Inquiry Threads Together Evidence on F.A.L.N Terrorism, N.Y. Times, April 17, 1977, at p. 1; Donner, The Age of Surveillance 459 (1980) (the FALN “is notorious for its unique indifference to personal injury and possible death randomly inflicted by bombs planted in public places”); Motley, US Strategy to Counter Domestic Political Terrorism 18, 76 (1983).
The background to the present case is the arrest in 1980 in a Chicago suburb of several members of the FALN, one of whom agreed to help the FBI’s investigation of the organization. He identified as members two of the people later charged in this case. FBI agents followed one, who unwittingly led the agents to an apartment in Chicago that was being used as an FALN safe house. The U.S. Attorney obtained from Chief Judge McGarr of the Northern District of Illinois an order authorizing the FBI to make surreptitious entries into the apartment to install electronic “bugs” and television cameras in every room. The FBI wanted to see as well as hear because it had reason to believe that the people using the safe houses, concerned they might be bugged, would play the radio loudly when they were speaking to each other and also would speak in code, and that the actual assembly of bombs would be carried on in silence. The television surveillance of the first apartment paid off: the FBI televised two of the defendants assembling bombs. On the basis of these observations the FBI obtained a search warrant for the apartment and found dynamite, blasting caps, guns, and maps showing the location of prisons. Tailing the same two defendants led to the second safe house involved in this appeal. Again a warrant was obtained to conduct electronic, including television, surveillance; and it was by televising meetings in this safe house that the other two defendants in this case were identified.
The trial judge held that there was .no statutory or other basis for Chief Judge McGarr’s order authorizing television surveillance of the safe houses and that therefore the fruits of the surveillance, including the videotapes, would be inadmissible in the defendants’ forthcoming trial. 583 F.Supp. at 105. The defendants and amici curiae advance the following additional grounds for this result: television surveillance in criminal investigations (other than of foreign agents) is forbidden by federal statute; it is in any event so intrusive — so reminiscent of the “telescreens” by which “Big Brother” in George Orwell’s 198k maintained visual surveillance of the entire population of “Oceania,” the miserable country depicted in that anti-utopian novel — that it can in no circumstances be authorized (least of all, one imagines, in the year 1984) without violating both the Fourth Amendment and the Fifth Amendment’s due process clause; and even if all this is wrong, still the particular orders (“warrants,” as we shall call them) in this case did not satisfy the requirements of the Fourth Amendment’s warrant clause.
The trial judge appears, however, to have overlooked United States v. New York Tel. Co., 434 U.S. 159, 168-70, 98 S.Ct. 364, 370-71, 54 L.Ed.2d 376 (1977), where the Supreme Court held that Rule 41 of the Federal Rules of Criminal Procedure, which authorizes the issuance of search warrants, embraces orders to install “pen registers” (devices that record the phone numbers that a telephone subscriber is dialing). See also Michigan Bell Tel. Co. v. United States, 565 F.2d 385, 388-89 (6th Cir.1977); United States v. Hall, 583 F.Supp. 717, 718-19 (E.D.Va.1984). Although the language of Rule 41 is that of conventional searches (see especially subsection (b)), the Court in the New York Telephone case read the rule flexibly and concluded that it covers “electronic intrusions” as well — including bugging. 434 U.S. at 169, 98 S.Ct. at 371 (dictum). We cannot think of any basis on which the rule might be thought sufficiently flexible to [878]*878authorize a pen register, bug, or wiretap, but not a camera. It is true that secretly televising people (or taking still or moving pictures of them) while they are in what they think is a private place is an even greater intrusion on privacy than secretly recording their conversations. But the fact that electronic eavesdropping is more intrusive than conventional searching did not prevent the Supreme Court in the New York Telephone case from reading Rule 41 — very broadly in view of its language— to embrace electronic eavesdropping. The next step, to television surveillance, is smaller than the one the Court took.
There is another basis, besides Rule 41, for the issuance of warrants for television surveillance. Like the power to prescribe or regulate procedure, to punish for con-tempts of court, and to issue writs in aid of the court’s jurisdiction, the power to issue a search warrant was historically, and is still today, an inherent (by which we mean simply a nonstatutory, or common law) power of a court of general jurisdiction. Indeed, it is an aspect of the court’s power to regulate procedure. A search warrant is often used to obtain evidence for use in a criminal proceeding, and is thus a form- of (or at least an analogue to) pretrial discovery. Although Congress can limit the procedural authority of the federal courts — if nothing else, Congress’s power to create lower federal courts (Art. I, § 8, cl. 9) so implies — until it does so with respect to a particular subject the courts retain their traditional powers. Rule 57(b) of the Federal Rules of Criminal Procedure virtually so states. And much of federal criminal procedure, especially in the early days of the federal courts, was judge-made. Orfield, Early Federal Criminal Procedure, 7 Wayne L.Rev. 503 (1961), gives a number of examples, though none involve search warrants. See id. at 529.
In England the inherent judicial power to issue warrants (warrants to seize persons and things and therefore implicitly to search for them) goes back very far — perhaps to the twelfth century. See Baker, An Introduction to English Legal History 15 (2d ed. 1979); Crown Pleas of the Wilt-shire Eyre, 1249, at 75, 92, 98, 100 (Meetings ed. 1961). By the seventeenth century the power was firmly lodged in the justices of the peace. See Dalton, The Countrey Justice 1619, at 300-06 (1972 reprint ed. [1622]); Lasson, The History and Development of the Fourth Amendment to the United States Constitution 36 n. 86 (1937). Hale’s History of the Pleas of the Crown (1736) makes clear that the justices of the peace could issue search warrants, provided they were not general warrants. See passages quoted in Scarboro & White, Constitutional Criminal Procedure 21 (1977). As the justices of the peace were not even lawyers, it seems likely that the judges of the royal courts (from which many features of the federal courts were borrowed) had the same power, if little or no occasion to exercise it. A modern American parallel is Rule 41(a) of the Federal Rules of Criminal Procedure, which in terms authorizes only federal magistrates and state-court judges to issue search warrants (see 3 Wright, Federal Practice and Procedure: Criminal 2d, pp. 571-73 nn. 1-7 (1982)) but has been uniformly assumed (for example in the New York Telephone case) to empower federal district judges as well to issue search warrants.
Although Entick v. Carrington, 19 Howell’s State Trials 1029 (C.P. 1765), has been cited for the proposition that statutory authority was required in England for the issuance of search warrants, see, e.g., United States v. Finazzo, 583 F.2d 837, 843 (6th Cir.1978), summarily vacated on other grounds, 441 U.S. 929, 99 S.Ct. 2047, 60 L.Ed.2d 657 (1979), the only issue in Entick was whether a nonjudicial officer (the secretary of state, described in the opinion as “the king’s private secretary,” 19 Howell’s State Trials at 1046) had common law authority to issue a general warrant to investigate seditious libel. See id. at 1063-74. The court held he did not, but did not express doubt about the power of judicial officers to issue particularized warrants. Cf. Boyd v. United States, 116 U.S. 616, 629-30, 6 S.Ct. 524, 531-32, 29 L.Ed. 746 (1886); Lasson, supra, at 47-49; cf. id. [879]*879at 34-37, 51-78; Dickerson, Writs of Assistance as a Cause of the Revolution, in The Era of the Revolution 40, 75 (Morris ed. 1939).
The power to issue a search warrant is a common law power in America as well as England, see Adams v. New York, 192 U.S. 585, 598, 24 S.Ct. 372, 375, 48 L.Ed. 575 (1904); Boyd v. United States, supra, 116 U.S. at 623, 6 S.Ct. at 528; United States v. Maresca, 266 Fed. 713, 721 (S.D.N.Y. 1920) (Hough, J.), and in the federal system as well as in the states. While “the whole criminal jurisdiction of the courts of the United States [is] derived from Acts of Congress,” Jones v. United States, 137 U.S. 202, 211, 11 S.Ct. 80, 83, 34 L.Ed. 691 (1890), this does not mean that every procedural incident of their jurisdiction is statutory. Until 1917 there was no general statutory authorization for the issuance of federal search warrants; yet it is hard to believe that before then no warrants were issued outside of the few specific areas (discussed in United States v. Jones, 230 Fed. 262, 265-68 (N.D.N.Y.1916)) in which Congress had explicitly authorized their issuance, usually by United States Commissioners. So we are not surprised to have found cases which assume as if it were an uncontroversial proposition that federal courts could issue such warrants before 1917. See Weeks v. United States, 232 U.S. 383, 34 S.Ct. 341, 58 L.Ed. 652 (1914); In re Jackson, 96 U.S. (6 Otto) 727, 733, 24 L.Ed. 877 (1878); Agnello v. United States, 290 Fed. 671, 677 (2d Cir.1923); but cf. United States v. Jones, supra, 230 Fed. at 268. We are only surprised not to have found more such cases.
In 1917 Congress enacted as part of the Espionage Act its first and last general authorization to federal courts to issue search warrants. See 40 Stat. 228-230, 18 U.S.C. §§ 611-633 (1940 ed.). Judging from the committee reports, Congress seems not to have thought it was granting the courts a new power as distinct from creating a procedural framework for the exercise of an old one, cf. H.R.Conf.Rep. No. 65, 65th Cong., 1st Sess. 20 (1917); H.R.Conf.Rep. No. 69, 65th Cong., 1st Sess. 20 (1917), although the floor debates indicate that a number of Congressmen — and the Attorney General of the United States — thought that without the new statute the federal courts would be helpless to authorize search warrants outside of the specific areas covered by previous statutes authorizing search warrants. See 55 Cong. Rec. 1838-39, 2065 (1917).
When Congress overhauled the federal criminal code in 1948, it repealed most of the search-warrant provisions of the Espionage Act, see Notes of Advisory Committee on Fed.R.Crim.Proc. 41, thereby leaving the matter of search warrants to be governed by rule of court. This broad delegation suggests that Congress views the issuance of federal search warrants as standing on a plane with other procedural powers that courts traditionally have exercised without explicit legislative direction. Additional evidence of this is found in the electronic-eavesdropping cases decided by the Supreme Court before the enactment in 1968 of Title III (of which more shortly), which explicitly authorized warrants for electronic eavesdropping. Osborn v. United States, 385 U.S. 323, 328-31, 87 S.Ct. 429, 432-34, 17 L.Ed.2d 394 (1966), upheld without mention of Rule 41 a federal court order authorizing a police officer to carry a concealed recording device, and. Katz v. United States, 389 U.S. 347, 354-56, 88 S.Ct. 507, 512-13, 19 L.Ed.2d 576 (1967), stated that a federal warrant could authorize bugging, and made only a passing reference to Rule 41(d) (execution and return). See id. at 355 n. 16, 88 S.Ct. at 513 n. 16. Other authorities for the inherent power of the federal courts to issue search warrants include United States v. Williams, 617 F.2d 1063, 1099 (5th Cir.1980) (en banc) (concurring opinion), and United States v. Yuck Kee, 281 Fed. 228, 230-31 (D.Minn.1922); see also United States v. Cafero, 473 F.2d 489, 499 (3d Cir.1973).
We shall not pretend greater certainty than we feel that the federal courts can authorize new types of search without statutory authorization, though New York [880]*880Telephone is powerful authority. The historical evidence we have marshaled is, as so commonly is the case, incomplete and enigmatic; and the floor debates on the 1917 search-warrant provisions are contrary to our position, as is Congress’s quick passage of a statute to permit searches for “mere evidence” after the Supreme Court held that the Fourth Amendment did not forbid such searches. See 18 U.S.C. § 3103a; 3 Wright, supra, § 664, at pp. 607-08. But a conclusion that neither Rule 41 nor the inherent common law powers of the federal courts allow warrants for television surveillance would have a most curious implication that in combination with all else we have said persuades us to reject it. A search without a warrant certainly is permissible in an emergency, see, e.g., Welsh v. Wisconsin, — U.S. -, 104 S.Ct. 2091, 2097, 80 L.Ed.2d 732 (1984); Warden v. Hayden, 387 U.S. 294, 297-99, 87 S.Ct. 1642, 1645-46, 18 L.Ed.2d 782 (1967); and a situation in which the FBI had strong reason to believe that an organization was operating a bomb factory but the FBI could not obtain a warrant to conduct the only type of search that would be effective in obtaining necessary evidence of this, because no court had been given authority to issue such a warrant, could fairly be described as an emergency. Therefore the government would have an argument that the fruits of such a search, though it had been conducted without a warrant, would be admissible in the criminal proceeding, provided the search was otherwise reasonable (an important qualification, as we shall see). A holding that federal courts have no power to issue warrants authorizing television surveillance might, therefore, simply validate the conducting of such surveillance without warrants. This would be a Pyrrhic victory for those who view the search warrant as a protection of the values in the Fourth Amendment.
The defendants argue, however, that Title III of the Omnibus Crime Control and Safe Streets Act of 1968, 18 U.S.C. §§ 2510-2520, as amended by the Foreign Intelligence Surveillance Act of 1978, 50 U.S.C. §§ 1801 et seq., deprives the federal courts of the power they would otherwise have to issue a warrant for television surveillance. Title III authorizes federal judges to issue warrants (called “orders”) for wiretapping and bugging, and establishes elaborate requirements for such warrants. See 18 U.S.C. §§ 2516, 2518. But it does not authorize warrants for television surveillance. People v. Teicher, 52 N.Y.2d 638, 652, 439 N.Y.S.2d 846, 853, 422 N.E.2d 506, 513 (1981); Sponick v. City of Detroit Police Dep’t. 49 Mich.App. 162, 198, 211 N.W.2d 674, 690 (1973); Carr, The Law of Electronic Surveillance 124 (1977). The statute regulates only the “interception of wire or oral communications.” 18 U.S.C. §§ 2516(1), 2518(1); see also 18 U.S.C. §§ 2511-2513, 2515, 2517, 2519. A man televised while silently making a bomb is not engaged in any form of communication, let alone “wire or oral communication.” Any possible doubt on this score is dispelled by the statutory definition of “intercept” as “the aural acquisition of the contents of any wire or oral communication through the use of any electronic, mechanical, or other device.” 18 U.S.C. § 2510(4) (emphasis added). A visual observation is in no possible sense an “aural acquisition,” or an acquisition, of any kind, of a “wire or oral communication.” Nor would a camera meet the statutory definition of “electronic, mechanical, or other device.” See 18 U.S.C. § 2510(5). The Senate committee report, after repeating the statutory definition of “aural acquisition,” remarks: “Other forms of surveillance are not within the proposed legislation.” S.Rep. No. 1097, 90th Cong., 2d Sess. 90 (1968), U.S.Code Cong. & Admin.News 1968, 2112, 2178.
It does not follow, however, that because Title III does not authorize warrants for television surveillance, it forbids them. The motto of the Prussian state — that everything which is not permitted is forbidden — is not a helpful guide to statutory interpretation. Television surveillance (with no soundtrack) just is not within the statute’s domain. The legislative history does not refer to it, probably because television cameras in 1968 were too bulky and [881]*881noisy to be installed and operated surreptitiously. It would be illogical to infer from Congress’s quite natural omission to deal with a nonproblem that it meant to tie the federal courts’ hands when and if the problem arose.
The defendants appeal to the spirit of Title III, which was, they say, the protection of privacy, and from which they infer that Congress meant to forbid any electronic investigative techniques that it did not authorize. But this description of the spirit of Title III is incomplete. Enacted in the wake of Katz v. United States, supra, which had held that electronic eavesdropping was subject to the Fourth Amendment, Title III established procedures to facilitate the use of wiretapping and bugging (subject to appropriate safeguards) in federal criminal investigations. Protecting privacy was a goal of the statute but not the only or even the paramount goal. The Senate report states that “Title III has as its dual purpose (1) protecting the privacy of wire and oral communications, and (2) delineating on a uniform basis the circumstances and conditions under which the interception of wire and oral communications may be authorized.” S.Rep. No. 1097, 90th Cong., 2d Sess. 66 (1968), U.S.Code Cong. & Admin.News 1968, 2153. The second formulation seems an allusion to the law-enforcement objectives of Title III, elsewhere in the report described as paramount. “[T]he major purpose of title III is to combat organized crime”; and “intercepting the communications of organized criminals is the only effective method of learning about their activities.” Id. at 70, 72, U.S. Code Cong. & Admin.News 1968, 2157, 2159.
The Foreign Intelligence Surveillance Act establishes procedures for electronic surveillance of foreign agents. Reflecting changes in technology in the decade that had passed since the enactment of Title III, the Act defines electronic surveillance broadly enough to cover television, by including in the definition the use of “an electronic, mechanical, or other surveillance device ... for monitoring to acquire information, other than from a wire or radio communication ____” 50 U.S.C. § 1801(f)(4); see S.Rep. No. 604, 95th Cong., 2d Sess., pt. 1, at 35 (1977), U.S. Code Cong. & Admin.News 1978, 3904, at 3936. Although the procedures in the Act have no direct application to this case— these defendants are not agents of a foreign power, and the government does not argue that the Act authorized television surveillance of them — the Act also amended Title III as follows: “procedures in [Title III] and the Foreign Intelligence Surveillance Act of 1978 shall be the exclusive means by which electronic surveillance, as defined [in the Foreign Intelligence Surveillance Act], and the interception of domestic wire and oral communications may be conducted.” 18 U.S.C. § 2511(2)(f). The defendants read this to mean that television surveillance, a form of electronic surveillance that does not involve the interception of wire or oral communications, may be conducted only in accordance with the Foreign Intelligence Surveillance Act; since that Act did not authorize the surveillance in this case, section 2511(2)(f) forbids it.
All this section means to us, however, is that the Foreign Intelligence Surveillance Act is intended to be exclusive in its domain and Title III in its. The powers that the Act gives the government to keep tabs on agents of foreign countries are not to be used for purely domestic investigations, and conversely the limitations that Title III places on wiretapping and bugging are not to be used to hobble the government’s activities against foreign agents. To read the Foreign Intelligence Surveillance Act as the defendants would have us do would give a statute designed to regularize the government’s broad powers to deal with the special menace posed by agents of foreign powers the side effect of curtailing the government’s powers in domestic law enforcement. This is not what Congress intended in making what the Senate report on the bill that became the Foreign Intelligence Surveillance Act described as a “technical and conforming” amendment to Title III. S.Rep. No. 604, supra, at 3.
[882]*882It is true that the committee reports describe section 2511(2)(f) as the “exclusive congressional statement on the question of the Executive’s power to order electronic surveillance,” id. at 63; see also S.Rep. No. 701, 95th Cong., 2d Sess. 71-72 (1978); H.R.Conf.Rep. No. 1720, 95th Cong., 2d Sess. 35 (1978), U.S.Code Cong. & Admin. News 1978, at 3965, and on this language can be built an argument that Congress intended in section 2511(2)(f) to take away not only the power the courts would otherwise have under Rule 41 or common law principles to issue warrants for television surveillance outside the scope of the Foreign Intelligence Surveillance Act, but also the President’s implicit power, deriving from Article. II of the Constitution, to use television surveillance for the protection of national security, other than as permitted by that Act. But the background of the quoted language makes this a weak argument. The Foreign Intelligence Surveillance Act is about national security; and much concern was expressed in the debates about the constitutionality as well as the prudence of Congress’s displacing by legislation the President’s implicit authority under Article II to protect the nation’s security against intrigues by foreign powers. See, e.g., 124 Cong.Rec. 28137 (1978) (remarks- of Representative Butler). The debate was resolved in favor of the proposed legislation. But the question whether to curtail executive power in domestic criminal investigations was not on the legislative agenda and so far as we can determine was not intended to be answered by the brief discussion in the committee reports of a “technical and conforming” amendment to Title III.
The fact is that Congress has never addressed the issue of judicial authorization of television surveillance in federal criminal investigations. But of course that observation cannot be the end of our analysis. It is too late in the day to argue that the Fourth Amendment regulates only the types of search that were technically feasible in the eighteenth century. The government therefore quite properly does not argue that television surveillance is outside the scope of the Fourth Amendment. We think it also unarguable that television surveillance is exceedingly intrusive, especially in combination (as here) with audio surveillance, and inherently indiscriminate, and that it could be grossly abused — to eliminate personal privacy as understood in modern Western nations.
The precise application of the Fourth Amendment to television surveillance has, therefore, now to be considered. The Fourth Amendment provides: “[1] The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and [2] no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.” The usual way in which judges interpreting the Fourth Amendment take account of the fact that searches vary in the degree to which they invade personal privacy is by requiring a higher degree of probable cause (to believe that the search will yield incriminating evidence), and by being more insistent that a warrant be obtained if at all feasible, the more intrusive the search is. See, e.g., Gooding v. United States, 416 U.S. 430, 464-65, 94 S.Ct. 1780, 1797-98, 40 L.Ed.2d 250 (1974) (dissenting opinion); United States v. Karo, — U.S.-, 104 S.Ct. 3296, 3304-OS, 82 L.Ed.2d 530 (1984). But maybe in dealing with so intrusive a technique as television surveillance, other methods of control as well, such as banning the technique outright from use in the home in connection with minor crimes, will be required, in order to strike a proper balance between public safety and personal privacy. Cf. United States v. Preston, 468 F.2d 1007, 1010 (6th Cir.1972); Nueslein v. District of Columbia, 115 F.2d 690, 696 (D.C. Cir.1940); Brinegar v. United States, 338 U.S. 160, 183, 69 S.Ct. 1302, 1314, 93 L.Ed. 1879 (1949) (Jackson, J., dissenting); 1 La-Fave & Israel, Criminal Procedure § 3.3, at p. 187 (1984). That question is not before us, but we mention it to make clear that in [883]*883declining to hold television surveillance unconstitutional per se we do not suggest that the Constitution must be interpreted to allow it to be used as generally as less intrusive techniques can be used. The first clause of the Fourth Amendment guarantees the right of the American people to be free from unreasonable searches by federal (and by judicial interpretation of the Fourteenth Amendment, state) officers; and a search could be unreasonable, though conducted pursuant to an otherwise valid warrant, by intruding on personal privacy to an extent disproportionate to the likely benefits from obtaining fuller compliance with the law. “[Tjhere can be no ready test for determining reasonableness other than by balancing the need to search against the invasion which the search entails.” Camara v. Municipal Court, 387 U.S. 523, 536-37, 87 S.Ct. 1727, 1735, 18 L.Ed.2d 930 (1967).
But we do not think there can never be a case where secretly televising people in private places is reasonable. The facts of the present case argue against so absolute an approach. The FALN has the plans, the materials, and the know-how to kill in gross. A sophisticated as well as lethal practitioner of urban terrorism, it meets to plan its operations and assemble bombs in safe houses leased under false names. Alert to the possibility that its safe houses might be bugged by the FBI, it takes effective steps to defeat this form of electronic surveillance, making it highly resistant to conventional methods of law enforcement even as enhanced by modern techniques for overhearing conversations. We do not think the Fourth Amendment prevents the government from coping with the menace of this organization by installing and operating secret television cameras in the organization’s safe houses. The benefits to the public safety are great, and the costs to personal privacy are modest. A safe house is not a home. No one lives in these apartments, amidst the bombs and other paraphernalia of terrorism. They are places dedicated exclusively to illicit business; and though the Fourth Amendment protects business premises as well as homes, e.g., Marshall v. Barlow’s Inc., 436 U.S. 307, 311-12, 98 S.Ct. 1816, 1819-20, 56 L.Ed.2d 305 (1978), the invasion of privacy caused by secretly televising the interior of business premises is less than that caused by secretly televising the interior of a home, while the social benefit of the invasion is greater when the organization under investigation runs a bomb factory than it would be if it ran a chop shop or a numbers parlor. There is no right to be let alone while assembling bombs in safe houses.
Having concluded that the district court could validly authorize television surveillance in this case, we come to the question whether the two warrants complied with the requirements of the Fourth Amendment’s warrant clause. On this aspect of-the case the defendants do not argue that the warrants were not issued on the basis of an oath and probable cause, but that they are not particular enough to satisfy the requirements of the Fourth Amendment. (They also make two highly technical objections to the warrants, which we shall take up last.)
The government asked for the'warrants in its applications for Title III warrants — applications the government had to make because it wanted to record the sounds in the apartments at the same time that it was televising the interiors — and the warrants it got covered both methods of surveillance. Title III imposes many restrictions on intercept warrants. Those related to the constitutional requirement of particularity are that the judge must certify that “normal investigative procedures have been tried and have failed or reasonably appear to be unlikely to succeed if tried or to be too dangerous,” 18 U.S.C. § 2518(3)(c), and that the warrant must contain “a particular description of the type of communication sought to be intercepted, and a statement of the particular offense to which it relates,” § 2518(4)(c), must not allow the period of interception to be “longer than is necessary to achieve the objective of the authorization, nor in any event longer than thirty days” (though re[884]*884newals are possible), § 2518(5), and must require that the interception “be conducted in such a way as to minimize the interception of communications not otherwise subject to interception under [Title III],” id. Each of these four requirements is a safeguard against electronic surveillance that picks up more information than is strictly necessary and so violates the Fourth Amendment’s requirement of particular description. Cf. United States v. Terry, 702 F.2d 299, 312 (2d Cir.1983); Carr, supra, § 5.07[1] at p. 256.
After stating that there was probable cause to believe both that the individuals named in the warrant were using the specified premises (the safe house) in connection with specified federal crimes and that intercepts of oral and wire communications at this address would yield evidence concerning these crimes, after stating that normal investigative methods had been tried and had failed, and after authorizing intercepts at the address, each of the original warrants in this case went on to authorize the FBI “to install [at the address] devices that will visually monitor and record the activity taking place in furtherance of the above-described [illegal] purposes.” Each warrant then specified the number of surreptitious entries that the FBI was authorized to make to install, adjust, and remove both the audio and video equipment (a total of 34 separate entries were authorized), required progress reports to be made to the court every five days, required that the electronic surveillance cease “upon the attainment of the authorized objective,” and put a deadline of 30 days on both the audio and video surveillance. One of the warrants was renewed a total of four times, so that it authorized a total of 150 days of surveillance, and the other was renewed twice; and in all, 130 hours of videotape were made. The renewal warrants were essentially identical to the original ones, but were supported by even more compelling showings of probable cause, based on information yielded by the execution of the original warrants.
In short, the warrants complied with all four of the requirements of Title III that implement the constitutional requirement of particularity. In fact, the only requirement of Title III that the government may not have complied with in its television surveillance was the requirement that the application be authorized by the Attorney General or an Assistant Attorney General specially designated by him. See 18 U.S.C. § 2516(1). Actually, the authorization was obtained; it just was not communicated to the district judge. We need not decide whether this was a failure to comply with the statute, (nothing in the statute suggests it is); it is in any event not relevant to the Fourth Amendment’s requirement of particularity.
A warrant for video surveillance that complies with those provisions that Congress put into Title III in order to implement the Fourth Amendment ought to satisfy the Fourth Amendment’s requirement of particularity as applied to such surveillance. Title III was Congress’s carefully thought out, and constitutionally valid (see, e.g., United States v. Ramsey, 503 F.2d 524, 530-31 (7th Cir.1974); United States v. Tortorello, 480 F.2d 764, 772-75 (2d Cir.1973)), effort to implement the requirements of the Fourth Amendment with regard to the necessarily unconventional type of warrant that is used to authorize electronic eavesdropping. In a conventional search the police go through a home or an office looking for contraband or evidence of a crime, and they either find what they are looking for or not, and then they leave. By rummaging through a person’s possessions in search of what they came for they invade the person’s privacy, and much of what they examine may be at once personal and irrelevant to the objective of the search, but the search is usually brief. Electronic interception, being by nature a continuing rather than one-shot invasion, is even less discriminating than a physical search, because it picks up private conversations (most of which will usually have nothing to do with any illegal activity) over a long period of time. Whether because it is more indiscriminate, or because people regard their conversations as more private [885]*885than their possessions, or for both reasons, electronic interception is thought to pose a greater potential threat to personal privacy than physical searches, and Congress therefore pitched the requirements for a valid intercept warrant higher than those for a conventional Rule 41 warrant: except for probable cause, the requirements in 18 U.S.C. § 2518 are not found in Rule 41. Television surveillance is identical in its indiscriminate character to wiretapping and bugging. It is even more invasive of privacy, just as a strip search is more invasive than a pat-down search, but it is not more indiscriminate: the microphone is as “dumb” as the television camera; both devices pick up anything within their electronic reach, however irrelevant to the investigation. If the government conducts television surveillance in conformity with the requirements of particularity that Title III imposes on electronic eavesdropping (not literal conformity, of course, since words such as “communications” and “intercept” in Title III do not fit television surveillance), the government has also conformed to the requirement of particularity in the Fourth Amendment’s warrant clause.
Since the government did this here, we need not, strictly speaking, decide what would happen if it had not done so. But because television surveillance is potentially so menacing to personal privacy, we want to make clear our view that a warrant for television surveillance that did not satisfy the four provisions of Title III that implement the Fourth Amendment’s requirement of particularity would violate the Fourth Amendment. Invoking our common law power to interpret the Constitution in a novel context, we borrow the warrant procedure of Title III, a careful legislative attempt to solve a very similar problem, and hold that it provides the measure of the government’s constitutional obligation of particular description in using television surveillance to investigate crime. We doubt that the government will resist this view, for there will be few if any cases where it does not try anyway to conform its application for a television-surveillance warrant to Title III. It wants the sounds as well as the sights, and it can get a warrant for the former only by complying with Title III; the soundtrack of a videotape, no less than a free-standing tape recording, is within the scope of Title III, as assumed in United States v. Haimowitz, 725 F.2d 1561, 1581 and n. 28 (11th Cir. 1984).
But we are unwilling to go further and hold that warrants for television surveillance are subject to Title III, as warrants for bugging and wiretapping are, so that if for example a television-surveillance warrant was destroyed without an order by the issuing judge, the person destroying it could be punished for contempt under 18 U.S.C. § 2518(8)(c), a provision of Title III that punishes unauthorized destruction of intercept warrants. It is only the requirements (listed earlier) of Title III that implement the constitutional requirement of particularity in the novel setting of electronic surveillance that we have borrowed to give content to the Fourth Amendment as applied to television surveillance. Of course it is anomalous to have detailed statutory regulation of bugging and wiretapping but not of television surveillance, in Title III, and detailed statutory regulation of television surveillance of foreign agents but not of domestic criminal suspects, in the Foreign Intelligence Surveillance Act; and we would think it a very good thing if Congress responded to the issues discussed in this opinion by amending Title III to bring television surveillance within its scope. But judges are not authorized to amend statutes even to bring them up to date. True, when statutes are ambiguous and judges interpret them in light of altered conditions, the result is very like amendment. “When a judge tries to find out what the government would have intended which it did not say, he puts into its mouth things which he thinks it ought to have said, and that is very close to substituting what he himself thinks right. Let him beware, however, or he will usurp the office of government, even though in a small way he must do so in order to exe[886]*886cute its real commands at all.” L. Hand, How Far Is a Judge Free in Rendering a Decision?, in The Spirit of Liberty 103, 108 (Dilliard 3d ed. 1960 [1935]). Judge Hand’s warning about judicial usurpation is apt here. When Congress has indicated the domain of a statute as clearly as it did when it enacted Title III, we cannot apply the statute outside its domain merely because we are confident that if Congress had known then what we know now it would have used more general language. Congress said in language that could not be clearer that Title III is about the interception of wire and oral communications and that interception means aural acquisition. There is no way in which these words can be read to include silent television surveillance; and the legislative history quoted earlier indicates that the exclusion from the scope of the statute of other methods of surveillance besides those defined in the statute was deliberate. Statutory language, to be stretchable, should be elastic. This statutory language is not. To read the words of this statute — intercept, aural, communication — as if they encompassed silent visual surveillance would be to say to Congress that there is no form of words that it can use to mark off the limits of a statute that will prevent aggressive, imaginative judges from disregarding those limits. And we naturally shrink from saying any such thing.-
If Title III and the Foreign Intelligence Surveillance Act were inconsistent, then we would have to make a choice, and in doing so we might unavoidably be exercising something resembling a legislature’s discretion. But there is no inconsistency. The two statutes govern nonoverlapping domains. And television surveillance for domestic criminal investigations is in neither statute’s domain. No doubt this is, as we have said, anomalous; it may seem fairly to cry out for congressional attention; but it does not create ambiguity as to the legal duties under which the government labors in conducting television surveillance of domestic criminal suspects. The only legal duties are those imposed by the Fourth Amendment. And we therefore go as far as is proper for us to go when we use a part of Title III to give meaning to the Fourth Amendment’s requirement of particularity as applied to television surveillance. Since the Fourth Amendment has long been held fully applicable to the states through the Fourteenth Amendment, state and local officers who might want to use television surveillance in criminal investigations will be under the same restraints as we impose on federal officers today.
The defendants complain, finally, that the warrants in this case did not explain the basis of the judge’s finding of probable cause and did not identify as safe houses the addresses at which the surveillance was to be conducted. This complaint misapprehends the purpose of a search warrant, which is twofold: to show that a judicial officer authorized the search (cf. Johnson v. United States, 333 U.S. 10, 13-14, 68 S.Ct. 367, 368-369, 92 L.Ed. 436 (1948)), and to indicate to the government agents who will execute the warrant what the limits of the authorization are (cf. Marron v. United States, 275 U.S. 192, 196, 48 S.Ct. 74, 76, 72 L.Ed. 231 (1927)). A warrant is not a judicial opinion, and the basis for the warrant is not in the warrant itself; as Rule 41(c)(1) makes clear, it is in the application for the warrant. The application in this case set forth in full and convincing detail the reasons for thinking that the addresses where the surveillance was to be conducted were FALN safe houses, that normal investigative methods would be unavailing, and that television surveillance was an appropriate supplement to electronic eavesdropping. The truth of the recitals in the applications is not controverted, and they provided an adequate factual basis for the warrants.
The order of suppression is reversed and the case remanded for trial.
Reversed and Remanded.