Journalists covering the Quebec courts will now be forbidden from publishing on Twitter or sending emails from the courtroom unless otherwise instructed by a judge.
Lawyers or journalists can keep their devices on vibrate or silent, unless they are deemed to be disturbing the proceedings.
Members of the public will have to keep their electronic devices off at all times.
The Quebec Superior Court said the new rules will come into effect on April 15.
Brian Myles, the president of the Quebec Federation of Journalists, said the province's justice system is taking a step backwards.
"Twitter was allowing us to be present in the courtroom and to inform our readers of the events and the witnesses and the testimony that were going on. Basically, [...] you're saying to the reporters 'Yes, you have to be there, we value freedom of the press, but could you please shut up,'" said Myles.
As as a result of the guidelines, journalists will have to step outside the courtroom to send information.
Myles said this will disrupt court proceedings and cause journalists to miss information that can often be valuable.
Many media organizations have been adopting the popular social media network, Twitter, to relay real-time information or break news to readers.