Article 21 of the Constitution of Japan unconditionally protects freedom of expression and prohibits censorship. Censorship is the suppression or alteration of speech or writing prior to publication in the interests of an alleged higher social good(1). The “After ‘Freedom of Expression?’" show at Aichi Triennale 2019 was attacked by hundreds of aggressive phone calls and an anonymous handwritten fax threatening arson. Nagoya Mayor Takashi Kawamura has demanded that a "comfort women" statue be removed. The Triennale organizers state that they made the decision to close the show three days after the opening in consideration of the threat of violence. There are opinions that criticize this decision as an act of self-censorship, and others that criticize the terror and hate speech that precipitated the closure.
While the strict meaning of censorship suggests the existence of some kind of supervisory body that preemptively reviews and deletes objectionable content before it is made public, such as has been seen in many societies during wartime or other large-scale states of emergency, and as is also common under totalitarian regimes, in recent years the word has come to be applied more broadly to all acts of suppression of expression.
In recent years, censorship have occurred in the case of Aichi Triennale 2019 and many other cases in Japanese society in response to the anonymous opinions from the public. Two major factors complicate these cases. One is the ambiguity over who has ultimate responsibility for the exhibitions, which are often organized by executive committees comprising art professionals, businessmen, politicians, and other advisors in conjunction with multiple levels of local and regional administration. The emphasis is on harmony rather than exchange of ideas, and there is a strong tendency among the involved parties toward conformity that diverges from international norms.
The other is that, as in many other countries today, the popularization of the internet and social networking sites since the turn of the century has accelerated the polarization of public opinion and encouraged the spread of online hate speech. This phenomenon presents new challenges to our evolving understanding of freedom of expression and what, if any, regulations should be applied to it.
(1) International Encyclopedia of the Social & Behavioral Sciences, 2001