Sami Al-Arian, the former University of South Florida professor due to be released from prison next month after pleading guilty to a charge of helping terrorists, may instead spend additional time in jail for refusing to testify before a grand jury, according to The Washington Post.

Mr. Al-Arian was arrested in 2003 and accused of conspiring to incite suicide bombings in Israel, Gaza, and the West Bank. He was subsequently dismissed from his post as a tenured professor of computer engineering at the university. But after a high-profile trial, a jury found him innocent on eight changes and deadlocked on nine others. In May 2006, following negotiations with federal prosecutors, he pleaded guilty to a charge of aiding a terrorist organization. He was to serve additional prison time and then be deported.

According to his lawyers, prosecutors agreed informally during plea bargaining that Mr. Al-Arian would not be called to testify against Muslim charities that the government says have funneled money to terrorists. But now the government argues that nothing prevents prosecutors from seeking his testimony, and Mr. Al-Arian is to be transferred to a prison in Virginia to be held on contempt charges for refusing to testify. “The plea agreement is clear, unambiguous, and does not grant Al-Arian immunity from future grand jury subpoena,” said Dean Boyd, a spokesman for the Department of Justice.

A lawyer for Mr. Al-Arian, Jonathan Turley, accused the Justice Department of “setting a perjury trap” for the former professor, and also of having “daisy-chained three grand-jury investigations to prolong his incarceration.” —Lawrence Biemiller