Paul Chambers, found guilty of sending a menacing message after joking that he would blow up Robin Hood Airport, has had his conviction overturned by the High Court.
David Allen Green, Chambers' solicitor, sent two tweets on Friday after the judges handed their ruling down: "Win", and "Acquittal".
Chambers' tweet had not been a serious bomb threat, Lord Judge, Justice Owen and Justice Griffith Williams found. Jokes that can be reasonably seen to be "silly", in "bad taste", "empty bombastic" or "ridiculous banter", should not be seen as menacing, the judges said in their ruling (PDF).
"The language and punctuation [of the tweet] are inconsistent with the writer intending it to be or to be taken as a serious warning," said the judges.
Moreover, insufficient weight had been given to the reaction of law enforcement and security at the airport to the joke, the judges said. The authorities did not heighten security in the wake of the tweet.
"No evidence was provided to suggest that even minimal consequential protective measures were taken at the airport, or that the level of perceived threat was heightened," said the judges.
The offending tweet
Chambers' tweet, sent on 6 January, 2010, after snow closed Robin Hood Airport in Doncaster, read:
"Crap! Robin Hood Airport is closed. You've got a week and a bit to get your shit together otherwise I am blowing the airport sky high!!"
South Yorkshire police arrested Chambers two days later on suspicion of a bomb hoax. When questioned, he repeatedly told police that the tweet had been a joke, and not intended to be menacing.
Police said to the Crown Prosecution Service in February that there was no evidence that the tweet had been "anything other than a foolish comment posted on 'Twitter' as a joke for only his close friends to see".
Chambers was convicted in Doncaster Magistrates Court of breaching the Communications Act 2003, which makes it an offence to send a menacing message by electronics means.
A previous appeal by Chambers in Doncaster Crown Court was dismissed, but he was given leave to appeal again in the High Court. His fight against conviction attracted support from celebrities such as Stephen Fry and Graham Linehan, as well as thousands of Twitter users.
"Thanks so much to all of you. We couldn't have done this without you, we wouldn't have got close," Chambers wrote in a tweet on Friday.
On Friday, Chambers' MP Louise Mensch said on Twitter that the Crown Prosecution Service should apologise to him.
"CPS owe my constituent @pauljchambers and the country a huge apology for a shameful prosecution that should never have been brought," said Mensch.
The Conservative MP added in a further tweet that Parliament should look into the trial.
"Two years of a man's life, stress and massive public costs wasted over an obvious joke," Mensch posted on Twitter. "It is for Parliament to investigate actions here."
As a result of Friday's ruling, Chambers had a fine of £385 quashed, and was awarded costs.