In November 2010, Crown Court judge Jacqueline Davies, sitting with two magistrates, dismissed Chambers' appeal, saying that the electronic communication was "clearly menacing" and that airport staff were sufficiently concerned to report it.
Today, the Lord Chief Justice Lord Judge, sitting with Mr Justice Owen and Mr Justice Griffith Williams, said:
We have concluded that, on an objective assessment, the decision of the Crown Court that this 'tweet' constituted or included a message of a menacing character was not open to it.
On this basis, the appeal against conviction must be allowed.
More top news
It's all going on tonight - as belt of rain sweeps from in from the west - lively downpours will mean rumbles of thunder and hail
A baby boy, born yesterday into a disaster zone, has not yet been given a name as his family and his village wait for help.
Many survivors of the Nepal earthquake still desperately await basic practical help and the shadow of a health crisis looms large.