Apple’s high-profile 2016 fight with the FBI, in which the company challenged a court order commanding it to help unlock the iPhone of one of the San Bernardino terrorists, exemplifies how central the question of regulating government surveillance has become in U.S. politics and law. But scholarly attempts to answer this question have suffered from a serious omission. Scholars have ignored how government surveillance is checked by surveillance intermediaries: companies like Apple, Google, and Facebook that dominate digital communications and data storage and on whose cooperation government surveillance relies. This Article fills this gap in the scholarly literature, providing the first comprehensive analysis of how surveillance intermediaries constrain the surveillance executive: the law enforcement and foreign-intelligence agencies that conduct surveillance. In so doing, it enhances our conceptual understanding of, and thus our ability to improve, the institutional design of government surveillance.

Surveillance intermediaries have financial and ideological incentives to resist government requests for user data. Their techniques of resistance are proceduralism and litigiousness that reject voluntary cooperation in favor of minimal compliance and aggressive litigation; technological unilateralism, in which companies design products and services to make surveillance harder; and policy mobilization that rallies legislative and public opinion against government surveillance. Surveillance intermediaries also enhance the surveillance separation of powers: They make the surveillance executive more subject to interbranch constraints from Congress and the courts and to intrabranch constraints from economic and foreign relations agencies as well as from the surveillance executive’s own surveillance-limiting components.

The normative implications of this descriptive account are important and crosscutting. Surveillance intermediaries can both improve and worsen the surveillance frontier: the set of tradeoffs between public safety, privacy, and economic growth from which we choose surveillance policy. They enhance surveillance self-government—the democratic supervision over surveillance policy—when they mobilize public opinion and strengthen the surveillance separation of powers. But they undermine it when their unilateral technological changes prevent the government from exercising its lawful surveillance authorities.