A lurching effort to try five prisoners at Guantanamo Bay by military commission for the Sept. 11 attack came to an abrupt halt 18 months ago, and a judge is expected to decide as early as Monday whether he can break the impasse and get the case moving again.

The presiding military judge stopped proceedings in April 2014 when the lawyer for Ramzi Binalshibh, one of five men facing the death penalty for allegedly planning and aiding the plot, revealed that members of his defense team had been questioned by the FBI about a potential illegal breach of security rules.

A Justice Department team has now submitted a report on the FBI investigation that concludes no one from the Binalshibh team will be facing criminal charges at this time, according to defense lawyers who have seen it. The report is expected to be unsealed at Monday’s hearing.

But that is not necessarily the end of the matter. The possibility of criminal charges for a member of the defense team created a potential conflict of interest between Binalshibh and his civilian lawyer, James Harrington, who at least in theory was facing the prospect of criminal charges. The judge must decide how to resolve that issue.

One possibility is that the judge, Army Col. James Pohl, could remove Harrington, which would require the government to find a new civilian lawyer with the required security clearance qualified to handle the death penalty case. Lawyers gathering at the U.S. base in Cuba ahead of the hearing said that the judge seemed to be signaling he would find there is no conflict and the case should resume.

“He expects that we will move past the conflict issue,” James Connell, an attorney for defendant Ammar al-Baluchi, said after a closed-door meeting with the judge to discuss the case.

Harrington said that he could not be certain Binalshibh would agree to proceed with him as his attorney but that he believed the judge was losing patience with the latest in a series of events that have disrupted and delayed the case. “Realistically, Pohl has got to look at this and say time isn’t helping anything,” the attorney said.

The judge could also move to try Binalshibh separately from the other four defendants, an option opposed by the chief prosecutor, Army Brig. Gen. Mark Martins, who could appeal such a decision.

The five defendants were arraigned in May 2012 on charges that include terrorism and nearly 3,000 counts of murder in violation of the law of war for their alleged roles planning and aiding the attack on Sept. 11, 2001. They were transferred from CIA custody to Guantanamo in September 2006 and a previous effort to prosecute them by military commission was scuttled by an aborted attempt by the government to try them in civilian court.

Martins, though declining to estimate when the case could go to trial, said they are making methodical progress behind the scenes. “There is just no one who has lost interest in it. There is no one whose determination is flagging in all this,” he said. “We just keep pressing forward.”

The defendants have yet to enter pleas in the case, though the lead defendant, Khalid Sheikh Mohammed, has previously said he orchestrated the Sept. 11 plot.

They were last in court in February, when they were also trying to resolve the conflict issue. That hearing was quickly adjourned after four of the five defendants recognized a new courtroom interpreter as someone they had encountered while in CIA custody, during which they were subjected to the government’s program of “enhanced” interrogation that has been widely condemned by critics as torture.

The interpreter was quickly removed from the courtroom, but defense lawyers are now seeking to question him about conditions in the CIA prisons, among other matters. If the judge decides to let the pretrial hearing proceed, among the first issues to be dealt with is a defense request that the interpreter be ordered to give a deposition.

(AP)