A request by the US government for the personal details of three Twitter users as part of the Wikileaks inquiry has met resistance over concerns that it is an invasion of privacy.
Twitter was issued with a subpoena by the US government last month to release the personal details of people connected to Wikileaks, including founder Julian Assange, Bradley Manning, Dutch hacker Rop Gongrjp and member of parliament in Iceland Birgitta Jonsdottir.
But the trio is appealing, arguing against the release of their private information.
"What's at stake here is the ability to use the internet freely and privately, without the government looking over their shoulder," said Aden Fine, of the American Civil Liberties Union, according to the BBC.
Assange said the order was "an outrageous attack by the Obama administration on the privacy and free speech rights of Twitter's customers".
The US justice department defended the request for routine data as a standard investigative measure.
The judge will issue a written ruling on the appeal at a later date.
Whistleblowing site Wikileaks released thousands of US diplomatic cables last year.
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