When applied to cinema, the term 'censorship' often conflates two distinct practices: governmentally administered systems of control over the expression of political ideas in film; and systems of self-regulation operated by entertainment cinema industries to ensure that the content of films conforms to the moral, social, and ideological mores of their national culture. Except in periods of national emergency, such as wartime, authoritarian forms of censorship, exercised through the monopoly power of the State, have not been prominent features of twentieth century liberal democracies, and the explicit, routine supervision of film content by state institutions -- censorship as a form of official criticism -- has been largely the preserve of totalitarian regimes. Self-regulation, on the other hand, can be understood as a form of market censorship, in which those forces in control of the production process determine what may and may not be produced. The most effective form of market censorship prevents movies from being made rather than suppressing them after production, but in either guise, censorship is a practice of power, a form of surveillance over the ideas, images, and representations circulating in a particular culture. Because cinema has been an international industry almost from its inception, the two forms of censorship have constantly interacted to reinforce each other. But Hollywood's international dominance has also meant that its form of self-regulation has been the most important censorship practice in cinema history.
Although film has always been more closely regulated than other forms of communication, cinema censorship cannot be directly equated with censorship of the press or other publications, because, for most of their history, films have not been granted a legally protected status as speech. In a 1915 decision that established the legal status of cinema in the United States, the US Supreme Court declared the exhibition of motion pictures to be 'a business pure and simple, originated and conducted for profit', and not to be regarded 'as part of the press of the country or as organs of public opinion'. They were thus not protected by the First Amendment's guarantee of free speech, but liable to prior censorship by state and municipal authorities. This legal definition of cinema as outside the spheres of politics and art is itself an implicit form of censorship. As a result debates over the regulation of cinema have been primarily concerned with questions of whether the entertainment it provided had harmful effects on its individual viewers. In practice, the great majority of film censorship, at least in the English-speaking world, has been concerned more with the cinema's representations, particularly of sex and violence, than with its expression of ideas or political sentiments.
Both the basis on which the censorship of cinema was justified and the mechanisms by which it would be practised were already well established by the time of the Supreme Court's judgement. Although the details of censorship procedures varied from nation to nation, there was a striking similarity in the evolution of those mechanisms in the countries of Europe, the Americas, and Australasia. In the nineteenth century most of these countries divided public entertainment performances into two categories for regulative purposes. What was often called 'legitimate theatre' was distinguished from what was known in France as spectacles de curiosité, a category of commercialized amusement that included marionettes, cafés-concerts, magic shows, panoramas, animal exhibitions, and 'all travelling shows which lack either a permanent site or a solid structure'. In France, for example, theatrical censorship ceased in 1906, but because cinema was classed as a spectacle, its performances were still subject to the control of local authorities.
By 1906, as cinema exhibition began to move into dedicated buildings, municipal governments determined that it was necessary to license the 'nickelodeons' or 'penny gaffs' on grounds of public safety, since they were seen as firetraps and health hazards. The regulation of content was something of an afterthought to these environmental concerns. The principal anxieties were created by the fact that nickelodeons were hot, dark places, where children in particular might be 'influenced for evil by the conditions surrounding some of these shows'.
The proliferation of local controls over cinema exhibition led to the establishment of national institutions of industrial self-regulation in the United States, Britain, and other European countries. By 1908, municipal public safety regulations were being widely used as the pretext for local film censorship, a practice which was strongly opposed by the emerging national distribution industries, because such regulations interfered with the circulation of their product. The symbiotic relationship between the regulation of film content and the development of monoopoly structures within the industry is best illustrated by the creation of the American National Board of Censorship ( NBC) in 1909.
Just before Christmas 1908, New York's Mayor George B. McClellan closed all New York's movie theatres because