Security experts say that if Hillary Rodham Clinton retained her government security clearance when she left the State Department, as is normal practice, it should be suspended now that it is known her unprotected private email server contained top secret material.

“Standard procedure is that when there is evidence of a security breach, the clearance of the individual is suspended in many, but not all, cases,” said retired Army Lt. Gen. William Boykin, who was deputy undersecretary of defense for intelligence in the George W. Bush administration. “This rises to the level of requiring a suspension.”

A State Department official declined to comment on whether Mrs. Clinton still holds her clearance or whether it is under review by the Bureau of Diplomatic Security, which awards and suspends security clearances.