If you post on Facebook, other social media sites, or via your business website and allow comments, care must be taken to review the comments carefully and where potentially offensive or defamatory of a third party to remove them as soon as possible. If you don’t you could attract legal liability as a secondary publisher of the comments.
In a recent case in South Australia, Johnston v Aldridge  SADC 68, a plaintiff sued both the comment maker and the business who posted the original Facebook post in defamation. Even though the business itself had not made the defamatory remarks themselves the Court held that by making the original social media post, it had participated in the publication of the comments by creating the occasion for the comments to be made. The business was ordered to pay $100,000 in aggravated damages. The Court held that by making the original post, the business accepted the responsibility to monitor the comments and remove those which were inappropriate or suffer the consequences, even if there was substantial inconvenience attached to monitoring the comments.
The business was ordered to pay $100,000 in aggravated damages.
It must now be obvious that the laws that apply to publishing are just as much applicable to social media platforms and online publishing. If you use social media platforms for promotion, then you are in the business of publishing.