Extract (with a snip, plus some minor editing for clarity):
Media law expert and author of Blogging and Tweeting Without Getting Sued Mark Pearson said it was yet to be determined whether Twitter was responsible for the content published by its users.
... Mr Pearson said the case should serve as a warning to others who post similar material on social media.
"Any threat of defamation should send a wake up call to everybody using social media that they are now publishers and they come under the same laws as journalists and other publishers have been subject to for centuries," he said.
"Every one of these cases is a reminder that people should be cautious when they are tweeting or using social media and just because something is funny or satirical does not mean that it is safe.
"Particularly with Twitter, there are so few characters to play with, that it is very hard to both defame someone and to qualify for the defences that might be available."