The Fourth Amendment Forecloses a Foreign Intelligence Exception: A Brief Case Against the FISA Section 702 Program

Patrick G. Eddington

Yesterday, the Senate version of an extension of Section 702 of the Foreign Intelligence Surveillance Act (FISA) was leaked. It is a near carbon copy of the same bill that was roundly defeated in the House in late April. And like the House bill, the Senate legislation lacks the only thing that matters: a warrant requirement to search the stored data of Americans collected under the program. In that sense, the 702 program has always been at odds with the plain language of the Fourth Amendment, thanks entirely to the secret court that oversees the semisecret surveillance activity.

For years, the Foreign Intelligence Surveillance Court (FISC) has held that querying Section 702–acquired data with a US-person term is not a separate Fourth Amendment event and requires no warrant—the program need only be “reasonable” at the point of collection. That rests on a “foreign intelligence exception” the Foreign Intelligence Surveillance Court of Review (FISCR) read into the amendment in In re Directives, building on In re Sealed Case. Two arguments demonstrate that the exception is a judicial construction the Framers would not have recognized, much less supported.

The Framers Used Encryption and Did Not Write a National Security Exception. That Silence Was a Choice.

The Founding generation was habitual users of “codes and ciphers,” what we now call “encryption.” The Library of Congress’s James Madison Papers record that Madison “feared constantly that unauthorized people would seek to read his private and public correspondence” and that he used ciphers to defeat them, continuing well after the 1783 peace. Thomas Jefferson invented a cipher device and corresponded in code with Madison, John Adams, James Monroe, and Robert Livingston; Madison encrypted portions of the very correspondence in which he and Jefferson worked through the Bill of Rights. They knew exactly what a state interception apparatus looked like—Europe’s monarchies ran “black chambers” that opened and decoded mail—and Jefferson designed his cipher to defeat them.

Accordingly, the men who drafted the Fourth Amendment understood encryption, interception, and the foreign intelligence and wartime contexts in which a government most plausibly claims a need to read communications without individualized cause. And they did not write an exception into the amendment’s text. 

The words of the amendment are categorical—“persons, houses, papers, and effects … no Warrants shall issue, but upon probable cause … particularly describing the place to be searched”—with no foreign affairs or national security carve-out, even though the Constitution shows that the Framers knew how to write a narrow emergency provision when they wanted one (the Suspension Clause, for habeas corpus, “in Cases of Rebellion or Invasion”). 

Under the canon that expressing one thing implies excluding others, the absence of a national security exception in a document containing an express, cabined emergency clause is a choice, not a gap for courts to fill. The “foreign intelligence exception” supplies the carve-out the Framers declined to write.

Section 702’s Bulk Communications Collection Architecture Is a General Warrant, and “Reasonableness at Collection” Cannot Cure It.

The Fourth Amendment was written to abolish the general warrant—the writs of assistance that let British officers “rummage through homes in an unrestrained search for evidence.” Their vice was generality: suspicionless, exploratory searching of everyone’s papers. The particularity requirement is the direct answer to such affronts to a citizen’s constitutional rights.

Section 702 recreates that vice. Because it acquires communications “to, from, or about” foreign selectors—and entire “Internet transactions” upstream—it knowingly sweeps in Americans’ communications. The FISC concedes this, acknowledging the “substantial Fourth Amendment interests … implicated by the acquisition of communications of … United States persons” (FISC, Memorandum Opinion and Order, November 6, 2015, at 38). The government thus holds a standing repository of innocent Americans’ papers and reserves discretion to search it using Americans’ identifiers. That is the general warrant in modern dress.

In re Sealed Case never held that a foreign intelligence exception exists at all—it “assum[ed] arguendo” that FISA orders are not warrants and upheld the statute on reasonableness grounds, expressly declining to “decide the issue.” And it rested that reasonableness on the Supreme Court’s “special needs” cases—the same doctrine In re Directives later invoked—even while conceding, via City of Indianapolis v. Edmond, that the exception does not reach searches whose primary purpose is “to uncover evidence of ordinary criminal wrongdoing.” An FBI query run for “evidence of a crime” is exactly that. 

Directives added the decisive limit: It confined its holding to targets “reasonably believed to be located outside the United States.” A US-person query inverts that—it aims inward, at an American, using that American’s identifier. Directives approved a search aimed outward; querying aims the same database at the persons the Fourth Amendment most clearly protects.

Keith Governs the Inward-Facing Search.

In United States v. U.S. District Court for Eastern District of Michigan (Keith), a unanimous Supreme Court held that the Fourth Amendment requires a warrant before electronic surveillance of domestic threats, rejecting executive-defined reasonableness because intelligence gathering is “broad and continuing” and prone to “oversee political dissent”—borne out by the documented Section 702 abuses (searches of a member of Congress, a judge, and protesters). Keith reserved only “the activities of foreign powers or their agents.” That reservation turns on the object of surveillance, not the provenance of a database. A US-person query is not surveillance of a foreign power; it is a search for an American’s communications. Querying falls on the Keith side of the line, not the Directives side.

Why “Reasonableness at Collection” Fails.

The Fourth Amendment doesn’t leave reasonableness to judicial balancing for searches of papers—it specifies a warrant, on probable cause, with particularity. Treating the lawful foreign-directed acquisition as curing the domestic-directed query signals that the Fourth Amendment stops protecting your communications the moment the government acquires them. The general warrant’s two vices—suspicionless retention and suspicionless searching—compound rather than cancel. 

This is the live conflict: The Hasbajrami district court held that a query presumptively requires a warrant; the FISC’s own 2015 reasoning rested on the government’s assurance that misuse was “remote, if not entirely theoretical”—an assurance prior Privacy and Civil Liberties Oversight Board reports and the Department of Justice Office of the Inspector General’s October 2025 review refuted.

The Government’s Defenses Share Multiple Flaws.

Each executive branch response—lawful acquisition, incidental collection, Keith’s foreign reservation, the 2024 Reforming Intelligence and Securing America Act querying safeguards, and unworkability—treats the lawfulness of the foreign-directed acquisition as resolving the constitutionality of the domestic-directed query. It does not. The acquisition’s foreignness is what makes it reasonable; the query’s domesticity is what makes it a search of an American’s papers. No lawful collection upstream changes the character of the deliberate, identifier-based search downstream. Thus, the querying doctrine is not an application of the Fourth Amendment but an inversion of it.

Even more insidiously, federal law enforcement and intelligence community officials would have us believe that in the Section 702 context, meeting the Fourth Amendment’s core standard that government officials must have evidence of criminal conduct beforehand to obtain judicial authorization to search and seize persons, places, or things is simply too burdensome in the 21st century. As I’ve noted previously, that’s false and always has been. 

Whether rank-and-file House and Senate members will continue to fall for these Section 702 deceptions or finally reject them will determine whether or not Congress will finally reaffirm the Founders’ intent that government officials must “get a warrant” to come for you, your home, and your most sensitive data.

Source: https://www.cato.org/blog/fourth-amendment-forecloses-foreign-intelligence-exception-brief-case-against-fisa-section-702