That is a new and important paper by Sergei M. Guriev and Daniel Treisman, here is the abstract:
In recent decades, dictatorships based on mass repression have largely given way to a new model based on the manipulation of information. Instead of terrorizing citizens into submission, “informational autocrats” artificially boost their popularity by convincing the public they are competent. To do so, they use propaganda and silence informed members of the elite by co-optation or censorship. Using several sources–including a newly created dataset of authoritarian control techniques–we document a range of trends in recent autocracies that fit the theory: a decline in violence, efforts to conceal state repression, rejection of official ideologies, imitation of democracy, a perceptions gap between masses and elite, and the adoption by leaders of a rhetoric of performance rather than one aimed at inspiring fear.
Again, here is my related Bloomberg column from June 18.