The ruling was issued one day after a ban on sending emails or tweets from Quebec courts went into effect.
And it preceded a cross-examination of the case's main investigator, who delved into the secretive and often vulgar world of acronyms and twisted verbiage used by many on social media platforms.
Judge Diane Lahaie said she would issue reasons for her ruling later, but told journalists covering the trial that they must provide their names, the media organizations they work for, and their reasons for tweeting.
The ruling was prompted by concerns about the ages of the three accused and a publication ban on their identities, as well as those of the victims. Reporters wishing to tweet are required to sign authorization documents, spelling out restrictions on what could be transmitted, Lahaie said.
Other Canadian jurisdictions are weighing whether to allow tweets and texts from within courtroom walls. Many reporters use popular social media tools like Twitter to quickly relay information and draw readers to their websites.
But Quebec courtrooms became Twitter-free zones this week after the courts issued new guidelines banning the practice.
Ontario's Superior Court established a policy in December that allowed journalists and lawyers to use electronic devices in the province's courtrooms, at the discretion of a judge.
The directive, which came into effect Feb. 1, still bans members of the public from doing so.
The three teens in the Ottawa case are accused of luring other girls through Facebook and other social media to a housing complex in southeast Ottawa, where drugs, alcohol and violence were used to coerce the victims into prostitution.
Week two of the trial began Tuesday with defence lawyer Trevor Brown cross-examining Ottawa police Det. Carolyn Botting, the main investigator in the case.
What followed was a lesson in the underworld vernacular used by some to express themselves online.
Brown called into question Botting's ability to testify as an expert witness with knowledge of terms such as "thuggin" and "M.O.B." — words and phrases allegedly used by the accused girls as they lured other teens using Twitter, Facebook and text messages.
"Money Over Bitches," Botting said as she was asked to define the term M.O.B. — an acronym, raised during presentation of evidence earlier in the trial, allegedly used by one of the accused in a Twitter message.
"It means money is more important than women," said Botting. "Women can be discarded."
The phrase "Racked Up Shawty" was also allegedly used by one of the accused; Botting said it's used to describe a woman with a lot of money or jewelry.
The three accused teens — two were 15 and one was 16 when they were arrested in June, 2012 — have pleaded not guilty to dozens of charges, including human trafficking, sexual assault, abduction and procuring for prostitution.
They have pleaded not guilty to all counts and are each expected to testify on their own behalf at some point during the trial.
The accused and nine alleged victims, aged between 13 and 17, cannot be identified under a publication ban imposed under the Youth Criminal Justice Act.
If they are convicted, the Crown is asking that the three accused be sentenced as adults.
If found guilty of human trafficking, for example, a youth sentence would carry a maximum three years in custody, including time already served. The adult sentence on the same charge would net a convicted offender a minimum of five years and a maximum of 14 years behind bars.
Earlier in the trial, Botting testified that investigators discovered phone numbers on a cellphone for 29 men, or "johns," who became clients of the alleged prostitution ring.
One of the accused johns, who is expected to testify, is facing a charge of sexual assault in connection with the case.
The trial is expected to last four weeks.Suggest a correction