Tweeting is allowed from hearings in the Supreme Court, the highest court in the land, it was announced yesterday.
Supreme Court justices are "content" for journalists, members of the public and legal teams to use "live text based communications" to let the outside world know what is happening in the courtroom.
The move came in guidance published by the Supreme Court on its practice relating to the use of tweeting and other forms of communication in the "context of ongoing public and professional debate on the issue".
The green light was given as cases before the court do not involve interaction with witnesses or jurors, and because there is rarely any reason why what is said should not be placed immediately in the public domain.
A statement announcing the guidance pointed out: "Important exceptions include cases where there are formal reporting restrictions in place, family cases involving the welfare of a child, and cases where publication of proceedings might prejudice a pending jury trial.
"Those attending such cases will be informed by notices placed at the doors of the courtroom that restrictions are in place."
Lord Phillips, President of the Supreme Court, said: "The rapid development of communications technology brings with it both opportunities and challenges for the justice system.
"An undoubted benefit is that regular updates can be shared with many people outside the court, in real time, which can enhance public interest in the progress of a case and keep those who are interested better informed.
"We are fortunate that, by the time a case reaches the Supreme Court, there is very seldom any reason for any degree of confidentiality, so that questions about what should and should not be shared with those outside the courtroom do not usually arise.
"This means that we can offer a green light to tweeting and other forms of communication, as long as this does not disrupt the smooth running of the court."
The guidance is limited to the Supreme Court because of its unique role as the highest appeal court in the land.
Different considerations apply to other courts, for a range of legal reasons.