The Obama administration’s latest overuse of executive authority at Guantánamo Bay is a decision not to let lawyers visit clients in detention under terms that have been in place since 2004. Because these meetings pose little risk and would send a message about America’s adherence to the rule of law, the administration looks as if it is imperiously punishing detainees for their temerity in bringing legal challenges to their detention and losing.

In one case, the administration is saying that the Yemeni national Yasin Qasem Muhammad Ismail no longer has the right to meet with his counsel, David Remes, because his plea to be released was “terminated.” The Justice Department will only let them meet, it said in an e-mail to Mr. Remes, if he signs a new memorandum giving the government what Mr. Remes calls “absolute authority over access to counsel.”

A military officer would decide each time whether lawyer and client could meet. Mr. Remes could not use classified information he developed for the client without permission. He could not share what he learned from his client with other lawyers of detainees, as he could previously. He could not use it to help defend his client against criminal charges if the government brings them. He could not advocate for him with human rights groups.

Mr. Remes refused to sign. He and colleagues filed a motion this month with the federal magistrate handling disputes about lawyer-client visits at Guantánamo Bay. They argue that while their client is detained, “he retains the right to pursue any available legal avenues to obtain his release” and without “a full and fair opportunity to meet with counsel in a confidential privileged setting,” his “right to challenge his detention” means nothing.