Full Idea
The argument for restricting defamatory speech is that unrestricted speech makes it impossible, or too difficult, to distinguish between those who deserve a trustworthy reputation and those who don't - a distinction in society's best interests.
Gist of Idea
Allowing defamatory speech is against society's interests, by blurring which people are trustworthy
Source
John Charvet (Liberalism: the basics [2019], 03)
Book Reference
Charvet,John: 'Liberalism: the basics' [Routledge 2019], p.18
A Reaction
A nice example of appeal to the common good, in opposition to the normal freedoms of liberalism. An example of the Prisoner's Dilemma. Should assertion of the common good of a group be a prime value of liberalism?