Censorship

Censorship is the suppression of speech that is considered objectionable by the censor. From a libertarian perspective, the worst forms of censorship are those imposed by violence or the threat thereof. The reasoning is that when something is made unavailable for public viewing by non-coercive means, anyone else may (assuming that the means are available) make it available for public viewing again. Libertarians would object to a person or organization being forced to provide a venue for the dissemination of ideas he opposes. For example, libertarians believe that a radio station should not be required to give equal airtime to all candidates in an election. Libertarians have pointed out that free speech can only exist when property rights are protected.

Governments have at various times engaged in censorship to suppress obscenity, disclosure of government secrets, and dissident political opinions. In many European countries, Holocaust denial is illegal. Perhaps a particularly insidious form of censorship is that imposed by making companies and organizations liable for the actions of others. For example, in the case of Curley v. NAMBLA, an attempt was made to hold an organization accountable for inciting a person to violence because the criminal happened to be a member of the organization.

Libertarians are sometimes accused of promoting activities by advocating their legalization. The counter-argument is that if there are many activities that are immoral or impractical, but should nonetheless be legal because the harms of prohibition would outweigh the benefits of prohibition. Also, if the arguments against those activities are so strong, then the opponents of those activities should have no trouble refuting any arguments in favor of those activities. According to U.S. Supreme Court Justice Louis Brandeis, "If there be time to expose through discussion the falsehood and fallacies, to avert the evil by the process of education, the remedy to be applied is more speech, not enforced silence."

Chilling effects and meta-debate
Censorship tends to chill speech not only about the topic about which speech is explicitly proscribed, but also about related or similar topics. For example, a law against encouraging drug use could chill debate on drug legalization, because some of the arguments made in defense of legalization &mdash; e.g. that certain drugs are not particularly harmful &mdash; could be construed as encouraging drug use.

In some cases, suppression of speech extends beyond merely censoring discussion on a particular topic, to also suppress speech about the merits of suppressing speech. For example, a government may say, "No, you cannot own your own business; all property must be nationalized. And any who question this edit are subject to prosecution!" If the citizen then attempts to debate the censorship, saying, "But why can't we discuss it?" the government may then say, "The merits of closing the discussion about socialism are not open for debate." If the citizen then attempts to debate the censoring of the debate about the debate, this can lead to further levels of censorship.

Books and zines
Certain media are more vulnerable to censorship than others. Books can be published in large batches, with production then ceasing. There is then nothing for the government to shut down, because production has already stopped. But the books that have already been produced can still circulate via a highly decentralized market of independent booksellers. Likewise, there many underground zines dealing with edgy topics; these can be easily and cheaply produced by anyone with access to a computer that has a printer. Those interested in inciting panic about others' behavior and thinking are less likely to be able to provoke a fuss about a few well-worn controversial books or zines circulating here and there via informal networks than about a website that is instantly accessible to anyone with an Internet connection, or a book that can be found on the shelf at every branch of a major bookstore.

Internet
The Internet is particularly susceptible to being censored because servers must operate continuously in order to serve web pages. Because it is a computerized medium, messages can be efficiently searched for offending keywords, unless strong encryption is used. Webhosts can be subpoenaed for records and pressure can be applied to them, through the threat of costly litigation, to cut off access to certain customers.

Some controversial web-based organizations have gone underground, restricting public access to their sites and requiring those who want to read their content to request an account and go through a screening process. Although it is still usually possible for government agents to infiltrate, there is then not as much worry of media, casual users, and miscellaneous concerned citizens seeing content about which they will feel a duty (or perceive an opportunity) to raise a fuss. Another way of evading censorship is to trade content by peer-to-peer networks that do not rely on any centralized server that the government could shut down.

Pro-NAMBLA pages have been purged from Facebook and LiveJournal purged 500 discussion groups in an effort to wipe out discussion of paedophilia, rape, and sexual violence. Various countries have engaged in Internet censorship; for example, China instituted a Golden Shield web filtering program, and Australia has blocked 10,000 websites. Iran also has imposed many controls on Internet service providers in that country.