A federal court in Dallas, Texas has imposed a gag order on the jailed activist-journalist Barrett Brown and his legal team that prevents them from talking to the media about his prosecution in which he faces up to 100 years in prison for alleged offences relating to his work exposing online surveillance.

The court order, imposed by the district court for the northern district of Texas at the request of the US government, prohibits the defendant and his defence team, as well as prosecutors, from making "any statement to members of any television, radio, newspaper, magazine, internet(including, but not limited to, bloggers), or other media organization about this case, other than matters of public interest."

It goes on to warn Brown and his lawyers that "no person covered by this order shall circumvent its effect by actions that indirectly, but deliberately, bring about a violation of this order".

According to Dell Cameron of Vice magazine, who attended the hearing, the government argued that the gag order was needed in order to protect Brown from prejudicing his right to a fair trial by making comments to reporters.

But media observers seen the hearing in the opposite light: as the latest in a succession of prosecutorial moves under the Obama administrationto crack-down on investigative journalism, official leaking, hacking and online activism.

Brown's lead defence attorney, Ahmed Ghappour, has countered in court filings, the most recent of which was lodged with the court Wednesday, that the government's request for a gag order is unfounded as it is based on false accusations and misrepresentations.

The lawyer says the gagging order is a breach of Brown's first amendment rights as an author who continues to write from his prison cell on issues unconnected to his own case for the Guardian and other media outlets.