Privacy has an image problem. Over and over again, regardless of the forum in which it is debated, it is cast as old-fashioned at best and downright harmful at worst—anti-progressive, overly costly, and inimical to the welfare of the body politic. Yet the perception of privacy as antiquated and socially retrograde is wrong. It is the result of a conceptual inversion that relates to the way in which the purpose of privacy has been conceived. Like the broader tradition of liberal political theory within which it is situated, legal scholarship has conceptualized privacy as a form of protection for the liberal self. Its function is principally a defensive one; it offers shelter from the pressures of societal and technological change. So characterized, however, privacy is reactive and ultimately inessential.
So described, privacy is anything but old-fashioned, and trading it away creates two kinds of large systemic risk. First, privacy is an indispensable structural feature of liberal democratic political systems. Freedom from surveillance, whether public or private, is foundational to the capacity for critical self-reflection and informed citizenship. A society that permits the unchecked ascendancy of surveillance infrastructures cannot hope to remain a liberal democracy. Under such conditions, liberal democracy as a form of government is replaced, gradually but surely, by a form of government that I will call modulated democracy because it relies on a form of surveillance that I will call modulation: a set of processes in which the quality and content of surveillant attention is continually modified according to the subject’s own behavior, sometimes in response to inputs from the subject but according to logics that ultimately are outside the subject’s control. Second, privacy is also foundational to the capacity for innovation, and so the perception of privacy as anti-innovation is a non sequitur. A society that values innovation ignores privacy at its peril, for privacy also shelters the processes of play and experimentation from which innovation emerges. Efforts to repackage pervasive surveillance as innovation—under the moniker “Big Data”—are better understood as efforts to enshrine the methods and values of the modulated society at the heart of our system of knowledge production. In short, privacy incursions harm individuals, but not only individuals. Privacy incursions in the name of progress, innovation, and ordered liberty jeopardize the continuing vitality of the political and intellectual culture that we say we value.