Editor’s Note: This post offers a preview of the authors’ upcoming article in the Santa Clara Law Review: The Notice Paradox: Secret Surveillance, Criminal Defendants & the Right to Notice.

Despite the continuing torrent of disclosures concerning previously secret and wide-ranging government surveillance efforts, many criminal defendants are not getting notice of the secret surveillance authorities used in their cases. This is a serious problem—one felt acutely by defendants, but one that also has immense consequences for the public at large in an age of mass surveillance. To those whose liberty is not on the line, the right of criminal defendants to notice might seem like a narrow, procedural issue. It is not. In a world of multiplying surveillance techniques used in secret, the criminal defendant’s right to notice of surveillance used against him is vanishing—and this shift presents a fundamental obstacle for defendants, and a basic, structural problem for courts and the public.

Though few may realize it, the public today depends on the people it is desperately trying to put in prison—criminal defendants, often in terrorism cases no less—to litigate the privacy rights of millions. Indeed, the public is more likely to see terrorism defendants challenge the legality of mass surveillance than companies like AT&T and Verizon, who barely protested over the course of a decade whenever the government asked to spy on their customers. And because civil standing rules have hobbled the public’s ability to obtain informed, adversarial review of mass-surveillance programs, criminal cases are increasingly the only available venue for litigation over the government’s most sweeping spying efforts.

But defendants cannot challenge surveillance they don’t know about—and, at a time when more and more searches are electronic and invisible, notice has become more important than ever.

Today, it is clear that the government is regularly withholding notice of controversial surveillance techniques from criminal defendants. The government does not believe it must give notice when it relies on the NSA’s bulk collection of phone records under Section 215—and it has told courts as much. (The only criminal case in which a defendant has been able to challenge Section 215—United States v. Moalin—is the exception that proves the rule. The government’s use of Section 215 in that prosecution came to light only after the defendant’s conviction, when officials sought to defend the NSA phone-records program in the face of public outcry.) The government does not believe it must give notice when it relies on evidence “derived” from NSA surveillance under Executive Order 12,333—and it has told the New York Times as much. The government does not believe it must give notice when it uses stingrays or dirtboxes—which mimic cell towers—to track down suspects via their cellphone signals. And, for five years, the government failed to give notice to defendants whose prosecutions involved FISA Amendments Act surveillance based on a secret DOJ legal analysis that it still refuses to disclose.

The list goes on and on: one can reasonably surmise that the government does not believe it must give notice to defendants when its investigations rely on the CIA’s bulk collection of financial records, the DEA’s bulk collection of phone records, or the DEA’s routine scanning of license plates around the country.

Indeed, the DEA has even prepared training guides instructing its agents to engage in “parallel construction” to keep defendants permanently in the dark about information and tips received from intelligence agencies.

This refusal to give notice is contrary to defendants’ due process rights, is at odds with historical practice, and runs against the grain of key Fourth Amendment cases that entitle defendants to challenge evidence derived from unlawful searches. Without notice, defendants cannot even begin to trace the fruit of any poisonous tree back to its source. This, we argue, is a significant and troubling shift, driven by the increasing prevalence of secret electronic searches, and by the fact that the government is interpreting its notice obligations unilaterally, with almost no public or judicial oversight.

In a new article to be published in the Santa Clara Law Review, we survey recent disclosures concerning secret surveillance in the United States and the impact of such surveillance on criminal defendants’ right to notice. As we write:

Herein lies the Notice Paradox: at precisely the moment that novel and untested surveillance techniques are multiplying, one of the most essential restraints on illegal searches—notice—is fast disappearing. The paradox is a practical one, too. That is because the people the government deprives of notice will never know that it chose not to provide notice to them. . . . When the government deprives an individual of notice of a secret search, it short-circuits the adversarial process without any outward sign it is doing so. As a result, just when the provision of notice has become most critical to the protection of individual rights and to the development of the law, the government has found itself in almost total control of who learns about its secret searches, and when. Left to its own devices, the government is likely to be miserly in its provision of notice, leaving criminal defendants (or others harmed by surveillance) without the opportunity to litigate key issues of legality and constitutionality. This is how the government can use an extraordinary programmatic surveillance statute for five years without ever having to submit the law to an adversarial legal challenge. This is how a government can, with the blessing of only a secret court, rely on a statute that authorizes the collection of only “relevant” records to collect the phone records of millions of people every single day.

It is impossible for the law to keep pace with surveillance technology without notice. By depriving defendants of notice, the government prevents the public courts from resolving complex legal questions posed by mass surveillance technologies. Instead, the government is deciding for itself whether these novel techniques amount to Fourth Amendment searches or otherwise jeopardize defendants’ rights—questions that defendants and the public are entitled to have independent courts answer instead.

It wasn’t always like this. Today is not the first time courts have had to confront the government’s use of new technologies to carry out surreptitious searches. The use of secret wiretapping and electronic recording devices in criminal investigations posed similarly novel legal problems in the last century. The courts that addressed the legality of these methods—and laid down the rules governing their use—were able to do so only because defendants received notice of that surveillance. For instance, in Katz and Keith, the government publicly acknowledged that investigators had overheard the defendant’s conversations using bugs and wiretaps. In Kyllo, the defendant had notice that the government’s search warrant application relied on evidence gathered using thermal-imaging technology. And in Jones, the defendant had notice of the government’s use of GPS tracking in order to record his movements. All of these seminal Fourth Amendment decisions would have been impossible if the defendants had not received notice of the government’s secret searches.

While our article does not resolve all of the knotted legal and policy questions about when the government should provide notice of surveillance in criminal cases, it does seek to set the terms of that debate. We recount the historical and legal roots of the notice requirement, provide a comprehensive survey of recent disclosures about secret uses of surveillance and the government’s failure to honor the notice right, and suggest several legal and policy principles that should drive the discussion going forward. We hope that it is of use to academics and practitioners—including government officials—as these issues continue to play out in both public policy and legal arguments.