ALEXANDRIA, Va. — A federal judge has rejected pleas to end the jailing of a former Florida college professor — Sami Al-Arian — for refusing to testify before a grand jury investigating Muslim charities in Virginia.

Judge Gerald Lee held a 45-minute, closed-door hearing yesterday on requests by Al-Arian’s attorneys that the contempt order be lifted because there is no significant chance that the ex-professor will change his mind about testifying.

“The court is keeping him in confinement,” Al-Arian’s lead counsel, Jonathan Turley, said as he emerged from the hearing. He declined to elaborate, citing the sealed nature of the proceedings.

The prosecutor who summoned Al-Arian to Virginia, Gordon Kromberg, also refused to comment, citing grand jury secrecy rules.

Al-Arian, who taught computer science at the University of South Florida, was tried in Tampa in 2005 on charges stemming from allegations that he was Palestinian Islamic Jihad’s top leader in America. The jury acquitted him on eight charges and deadlocked on nine others. Last year, Al-Arian agreed to avert another trial by pleading guilty to one charge of providing aid to an embargoed terrorist group.

Al-Arian has asserted that he should not be required to testify before the grand jury because the government promised him during plea negotiations that he would not have to cooperate with federal prosecutors, including those in Virginia. He also contends that militants could target him as a collaborator if he testifies.

The judge who handled Al-Arian’s trial, James Moody Jr. ruled that the plea agreement did not excuse the former professor from testifying in Virginia. Judge Lee adopted that ruling. One federal appeals court upheld the decision, but a related appeal is still pending before another court.

“It’s just an outrage,” Al-Arian’s daughter, Laila, said after learning of the decision yesterday. “My father went on a hunger strike that almost took his life to make a statement that he wasn’t going to testify. It’s clear he still won’t testify, therefore keeping him in prison any longer is just punishment at this point. When a person’s held in civil contempt, it’s not supposed to be punitive.”

Sami Al-Arian was originally expected to complete his criminal sentence in April of this year. However, that sentence was put on hold while he serves up to 18 months for civil contempt. If the contempt citation is lifted, Al-Arian is expected to serve about four months more in prison before being deported under terms of his plea deal.

Al-Arian’s supporters also worry that prosecutors will seek to charge him with criminal contempt or obstruction of justice. “I think we have to suspect something like that may be in the offing,” a former attorney for Al-Arian, Peter Erlinder, said.

Yesterday’s court session took place in secret despite a formal request by this reporter that the hearing be opened to the public.

There is no public docket for the Virginia court proceedings, and no reference to them appeared on the list of hearings posted at the court yesterday. However, a judge in Florida released documents identifying Al-Arian as a recalcitrant grand jury witness and stating that the probe is focused on a Herndon, Va.-based educational charity, the International Institute for Islamic Thought.

One lawyer not involved in the Al-Arian case, Theodore Boutrous Jr., said judges seem more and more reluctant to cut short the jail stays of those held in contempt. He noted that two journalists, Judith Miller and Joshua Wolf, reached accommodations with prosecutors after spending substantial time in jail. Judges have “seen that the coercive effect has worked,” and at the end of the day, “they were able to get the testimony,” Mr. Boutrous said.