Here’s the abstract of the paper available on SSRN: “This review essay draws on recent books by Richard L. Hasen and Jacob Mchangama to reflect on the difficult tradeoffs faced by civil liberties advocates in the context of democratic backsliding.” Keck concludes:

[C]ontemporary liberal democracies face a difficult choice. They can extend full freedom of expression to deliberately false speech that undermines free and fair elections, on the theory that doing so will make it easier to maintain full freedom of expression for legitimate political opposition and dissent. If they make this choice, they should do so knowing that no one has yet demonstrated this causal connection. Alternatively, they can declare a red line marking speech deliberately undermining free and fair elections as out of bounds. If they make this choice, they should do so knowing that speech restrictions have a tendency to metastasize.

Mchangama and Hasen counsel different choices, but taken together, their books illuminate the stakes in key ways. Mchangama reminds us that the idea of free speech “as a principle to be upheld universally rather than a prop to be selective invoked” was achieved only after centuries of struggle and hence should be defended at all costs (id. at 392). Hasen, for his part, acknowledges that the Warren Court’s robust across-the-board protection of free expression in cases like Brandenburg “was right at the time because of the importance then—and now—of dissent against government action” (Hasen, at 24). But he suggests that in recent years, the key danger has shifted: “While we cannot dismiss the risk of censorship as an unintended consequence of reform, the greatest danger today is a public that cannot determine truth or make voting decisions that are based on accurate information, and a public susceptible to political manipulation through repeatedly amplified, data-targeted, election-related content, some of it false or misleading” (id.). In Hasen’s view, “[m]odern First Amendment doctrine should reflect [these] radically changed circumstances, albeit duly sensitive of the real dangers posed by government regulation” (id.).