Moral panic is a sociological phenomenon that the British researcher Stanley Cohen dealt with , and which he first described in his book Folk Devils and Moral Panics.
According to Cohen, this is a widespread panic that is spreading in society , according to which there is a moral problem that could threaten collective morality. The problem is presented, often using demagoguery or demonized by the media traditional and others, as well as occasionally by various interested parties (which Cohen calls "moral entrepreneurs") and its treatment is raised by them priority. Panic can occur either due to a new phenomenon, or an existing phenomenon in which a particular incident related to it ignited the media, for example preaching against alcoholism following a fatal car accident involving drunk drivers.
Cohen argues that it is sometimes possible to discern factors that initiate this phenomenon in order to accumulate some personal gain following the panic. On the other hand, sometimes the "moral entrepreneurs" believe completely and not cynically in the moral justification for panic.
The theory explains that more than once, the moral problem reports in a way that is disproportionate to the realistic dimensions of the problem, and sometimes even exaggerated data is presented to increase the moral panic that is spreading in society.
A classic example of moral panic is Punk culutre and how British society met it in the 70's. For this example and more on moral panic see Dick Hebdige: Subculture: The Meaning of Style.