Arian, 50, declined to comment. In the courtroom was a crowd of Arian’s supporters, includ ing nearly two dozen people from Tampa, where Arian taught computer engineering at the University of South Florida before his first arrest in 2004.

Arian was charged then with raising money and otherwise assisting Palestinian Islamic Jihad, a group the U.S. government declared a terrorist organization in 1995. At trial in 2005, he was acquitted on eight of 17 counts, and the jury deadlocked on the other counts.

Rather than face a retrial, Arian pleaded guilty in May 2006 to one count of conspiring to assist the terrorist group and was sentenced to 57 months in prison, most of which he had served while awaiting trial. In his plea agreement, Arian did not agree to cooperate with subsequent investigations, as most federal plea agreements require.

Within days of Arian’s plea and sentencing, prosecutors in Alexandria subpoenaed him to testify in the investigation of a group of Herndon organizations suspected of funneling money to terror groups, although no one has been charged. Arian refused, both in 2006 and 2007, and was jailed for civil contempt of court for nearly all of 2007.

“I refuse to testify,” Arian told the grand jury in 2007, “based on my prior plea agreement with the government that I’m not required to testify and cooperate in this or any other investigation. I refuse, therefore, to make any further statements.”

Last year, Alexandria prosecutors subpoenaed him for the third time and again offered him immunity from prosecution for his testimony. But the immunity order crafted by Assistant U.S. Attorney Gordon Kromberg contained additional language not usually found in such orders, saying that Arian could still be prosecuted for obstructing justice or for actions occurring after his testimony.

Arian’s attorneys protested, and Brinkema said in August, “I think it’s real scary and not wise for a prosecutor to provide an order to the court that does not track the explicit language of the statute.”

After Arian’s third refusal to testify, prosecutors obtained indictments in June charging him with two counts of criminal contempt of court. Brinkema postponed the trial while Arian appealed his case to the U.S. Supreme Court, but the court declined to consider the case.

Turley sought to have Brinkema dismiss the case, but the judge said, “There is nothing in the record that would indicate that the U.S. attorney in this district is barred, by the plea agreement in Florida, from bringing this action.” Brinkema said Kromberg’s immunity orders “did not materially change the scope of protection given to the defendant.”

Kromberg then asked whether the defense would be able to use the theory that Arian refused to testify based on the advice of his attorneys. Brinkema said yes, that a jury could consider it. That issue could become crucial to a jury trying to determine why Arian defied orders to testify.