Soon enough, the police will have the capacity to know almost everything about everyone. Not because most of us are suspected of doing anything wrong, but because indiscriminate data surveillance—“indiscriminate” meaning precisely that it is not driven by individualized suspicion of criminality—is accelerating rapidly. What policing agencies do not collect on their own, they are acquiring from data brokers, who are selling them thousands of points of information about ordinary people, much of it quite personal and sensitive: where we live and what we purchase, where we travel, what we do, with whom we communicate. Policing agencies are partnering with private technology vendors to mine that data, often using artificial intelligence, making suspects of us all.
This Article is an in-depth examination of the constitutionality of indiscriminate data. It reaches two conclusions. First, under either an originalist or doctrinal approach, the acquisition and querying in bulk of data concerning individuals suspected of no wrong is unconstitutional. It must cease. Second, the only way any version of indiscriminate data surveillance conceivably could be constitutional is if, prior to its being employed, there are policies in place that carefully regulate and cabin the practice, with the specifics of those policies then subject to constitutional review. Such policies must address matters such as who is surveilled, what data is collected, how that data is queried and for what purposes, and how long the data is retained. Even then, constitutional doubts remain.
No court even should consider upholding indiscriminate data surveillance until such a policy—preferably legislatively authorized—is in place, so the policy can be measured against constitutional requirements. Adopting the constitutional analysis in this Article will change the existing default presumption, from a status quo in which policing agencies forge forward without authorization, waiting to be stopped, to one in which they must seek formal permission before proceeding. If this occurs, many forms of indiscriminate data surveillance currently being employed no doubt will cease, and others—if they continue at all—will and should be subjected to strict limits and safeguards.