Military attorneys representing detainees at Guantanamo Bay, Cuba, will stop communicating in writing with their clients because the commander of the military detention center has authorized officials to review mail coming from detainees’ lawyers.

The chief military defense counsel for Guantanamo Bay has instructed the military attorneys in his office not to comply with the commander’s order that they sign an agreement allowing material marked attorney-client privilege to be inspected for possible “contraband” information.

Military defense attorneys said the prospect of government personnel, who answer to the commander, reading privileged communication before and during trials is impermissible under rules of professional conduct.

“We all have security clearances, but I guess they don’t trust us to abide by the rules,” said Marine Corps Col. Jeffrey Colwell, the chief military defense counsel. “You can’t defend your client without being able to communicate with him confidentially. Without that, the system fails.”

The dispute pits the lawyers’ understanding of their ethical obligations against the commander’s concern for security.

Late last month, Rear Adm. David Woods, who oversees the detention facility but is not involved in military commissions, said in an order that a “privilege team” of Defense Department lawyers, as well as intelligence and law enforcement personnel, would inspect the mail and report to him but not to military prosecutors.

“This inspection shall not include a review of the substantive content of the incoming mail,” according to the order, but would still include an effort to determine whether inappropriate information is being passed to a detainee. The order said contraband can include information about “current and political events in any country” if it is not related to a military commission proceeding; information about current or former detainees at Guantanamo Bay; and information about U.S. government personnel.

The last provision stems in part from the discovery of photos of CIA personnel in the cells of high-value detainees in 2009 after defense attorneys, trying to identify interrogators, gave images of them to their clients.

On Sunday, Colwell issued what he called strong guidance to the 40 attorneys under his command, including more than 30 military officers, instructing them not to follow Woods’s order and to stop sending privileged material to their clients. Colwell also said he had objections to an order on arranging face-to-face meetings between defense attorneys and detainees, and told the attorneys not to execute or sign that either.

“It is my opinion that these orders, and the following procedures established by them, do not allow you to adequately safeguard attorney-client privileged communications,” Colwell wrote in an e-mail to defense attorneys, including a pool of nearly 100 civilian lawyers who are on call in case the government begins more military commissions.

In his order, Woods said the procedures are comparable to those governing interaction between detainees and the lawyers challenging their detention under the writ of habeas corpus in federal court in Washington, D.C.

But Zachary Katznelson, a senior lawyer at the American Civil Liberties Union who has represented Guantanamo Bay detainees in federal court, said the communications of civilian lawyers in those cases are searched only for physical contraband and the materials are not read by the privilege team.

“In contrast, Woods defines contraband to include information,” Katznelson said. “He wants his monitors to read the contents of the communications and to possibly hold back — and potentially bring to his attention — information deemed outside the scope of representation. Critically, this would include any mention of U.S. personnel involved in torture and abuse of prisoners, even if directly related to the case. There is no such restriction on the habeas side.”

Navy Cmdr. Tamsen Reese, a spokesperson for the Joint Task Force at Guantanamo Bay, said Woods would not be commenting in advance of a hearing next week at the base.

Last year, the military judge overseeing the prosecution of Abd al-Rahim al-Nashiri, a Saudi facing capital charges in the bombing of the USS Cole in Yemen in 2000, ordered authorities at Guantanamo Bay not to read anything that is clearly marked attorney-client correspondence. Because of that, Colwell exempted Nashiri’s defense team from his instruction.

But the government may attempt to have the judge, Army Col. James Pohl, adopt Woods’s order in the Nashiri case at a pretrial hearing next week. Even if Pohl rejects any government motion, his ruling would still apply only to the Nashiri case. Judges have not yet been appointed to the cases of other detainees facing charges, and their attorneys have no judge to hear an appeal.