This blog post is a transcript of my opening remarks on the panel “Restoring Personal Privacy without Compromising National Security” at the 50 Years of the ACM Turing Award Celebration.


We now live in a world in which the rules coded into the technology we use plays as important a role in governing our lives as the formal laws written in the public law books. Code is law already, for better or worse. Unfortunately both the technology and policy communities still tend to treat technology as a simple set of tools, like a mechanical watch, home appliance, or automobile, which always unquestioningly serves its operator. A smart watch or home appliance can now monitor our behavior and report it to a company or government, can enforce remotely-controlled rules determining when and how it operates, and can remotely determine what content we are allowed to view or when and for whom the smart lock on a door to our own home opens. Today’s cars can already be remotely disabled or attacked, and soon will be capable of governing where we can go and when. Technology is no longer just a set of obedient tools but, for better or worse, also an inherent part of the system of governance that determines what individual freedoms we do and don’t have.

Unfortunately, the mindset of technology as an obedient toolset has led both government and industry to deploy technology in ways that undermine long-standing governance principles and undermine the basic freedoms and rights we depend on democratic governments to uphold: principles such as rule of law, separation of powers, and limited warrant-based search.

The principle of rule-of-law states that the public should have the right to know, debate, and challenge the rules that govern their lives. As technology is increasingly critical in enforcing the rules by which we live, we must demand and work to ensure that the rule-of-law principle translates properly into the digital domain. We have now have well-understood technology, especially cryptographic tools, that can ensure the integrity and correctness of publicly-known processes while keeping sensitive details private, consistent with rule-of-law principles. But so far we have seen little to development or deployment of these technologies for this purpose.

Instead, law enforcement and surveillance agencies have shifted ever deeper into the shadows. Ed Snowden and other whistleblowers cast much-needed light on the proliferating morass of secret law embodied not only formally in the secret proceedings of bodies such as the FISA court, but also the de facto secret law embodied in secret mass surveillance technologies, secret stockpiles of software exploits, and the secret agency-internal processes that purportedly govern their use. The secrecy and non-transparency of these processes are antithetical to democracy and rule of law, whether embodied in secret FISA decisions or in code and databases designed and deployed in secret by three-letter agencies.

Separation of powers is intended to prevent any branch of government from acquiring too much unaccountable power. We also have well-understood technology to split trust across multiple independently-operated authorities, such as Byzantine consensus and threshold cryptography, but again it is rarely used. In the “technology as dumb tool” mindset, government deploys law-enforcement and surveillence technologies largely in the domain of the executive branch. Only that one branch effectively has any understanding of, let alone control over, the deep technological rules and processes that determine what protections we do and don’t have from law-enforcement and surveillance. Legislative and judicial oversight becomes merely a fig-leaf, along with the whole principle of separation of powers, when no one in the legislature or judiciary actually has any understanding of, or control over, deep technology systems and processes deployed exclusively in the executive branch.

Finally, our Fourth and Fifth amendments are intended to impose strict limits on government searches for law-enforcement or surveillance purposes, recognizing that that it is more important to have democratic freedoms to defend than to catch every last criminal. But the obsolete mindset of technology as “dumb tools” has led many policy-makers to underestimate the centrality of personal devices in our lives. Policy-makers often treat personal devices such as laptops and smartphones, and the encrypted data they might contain, as mere possessions similar to the contents of one’s home, and claim that law-enforcement agencies are somehow entitled to access to these devices. However, this mindset neglects the reality that we now carry personal devices with us everywhere, using them as extensions of our thoughts and memories, and to intermediate our most intimate communications. While the possessions in our home enjoy Fourth Amendment protections against unreasonable search and seizure, the contents of our minds also have Fifth Amendment protections against self-incrimination. Even if I remember committing a crime, the government cannot force me to admit it, even with a warrant: that is, under human-rights principles my mind is a legitimate “warrant-proof space.” Now that we rely on mobile personal devices to help us remember and communicate wherever we travel, they have effectively become extensions of our minds and bodies – and as wearables and implants proliferate they will become only more so. We must recognize that our Fifth amendment protections are not complete or effective today unless they extend the warrant-proof space of our minds to the electronic extensions embodied in our personal devices.

There is no pure technology solution divorced from policy, but there is also no pure policy solution divorced from the reality of technology as a de facto policy-enforcement mechanism. We must intelligently integrate technology and policy to restore the trustworthiness of democratic processes, rights, and freedoms in the digital age. Again, we have the technology tools to accomplish this, but we must use them. Research on this topic that Joan and I and others have worked on has demonstrated how technology can be married with policy principles for a few proven law-enforcement processes such as private set-intersection of cell tower dumps and privacy-preserving contact chaining. We can and must design technology to uphold rule-of-law, by transparently enforcing public processes for law enforcement and surveillance while keeping details of investigations and non-targeted users private. We can and must design technology to enforce separation of powers, such that systems independently operated by each branch cooperate and keep each other in check in implementing electronic law-enforcement and surveillance processes. We must work to ensure that technology used in law-enforcement and surveillance verifiably adheres to the strict limits the Fourth Amendment allows for search of ordinary possessions and business records. Finally, our law-enforcement and surveillance technologies must respect the contents of our electronically-augmented minds as legitimate warrant-proof spaces essential to upholding our freedoms of thought, speech, and association.

In summary, we must discard the obsolete mindset of technology as merely a set of dumb tools and recognize that technology has become, for better worse, an integral part of our system of governance that determines what rights and freedoms we all do and don’t have. Technologists need to recognize this, and work closely with the policy community to ensure that the policy principles underlying our basic individual freedoms are not “lost in translation” to digital society.


The author wishes to thank Joan Feigenbaum for organizing the panel, and all the distinguished panelists for thought-provoking discussion and feedback on early drafts of this statement.