It became known last December that a Virginia grand jury investigating the whistleblower site WikiLeaks had issued subpoenas for the Twitter records of three supporters of the group, including a member of the Icelandic parliament. Now the ACLU believes it has evidence that four such demands were issued in secret and has asked a federal judge to make those applications public.

According to Wired, the ACLU's suspicions grew out of "an examination of case numbers of entirely-sealed dockets in U.S. District Court in Alexandria, Virginia." Wired notes that "while it’s been speculated that other companies have received 2703(d) orders besides Twitter, no other companies have gone public with such a demand."

In its appeal to the court -- filed in conjunction with the Electronic Frontier Foundation -- the ACLU acknowledges that it might be "appropriate to maintain certain documents under seal," but insists that it is "in violation of clear Fourth Circuit caselaw" and "simply not permissible" to keep the very existence of such applications a secret.

The ACLU and the EFF are currently helping to fight the court's demand for Twitter records on behalf of Seattle activist Jacob Appelbaum, Icelandic parliamentarian Birgitta Jonsdottir, and Dutch businessman Rop Gonggrijp. This latest appeal has been filed as part of that case.

In March, a federal judge denied a request to reject the demand for these records, arguing that because the government is only seeking to determine when these three individuals sent private messages to one another and from what IP addresses -- but not the actual content of those messages -- they lack standing to appeal.