U.S. government investigators subjected approximately 50 members of the Joint Staff to polygraph tests in August as part of an inquiry into leaks of classified information to the media.

The tests focused on whether military officers and civilian employees disclosed details about the U.S. military's diminished stocks of crucial munitions, including long-range missiles and Patriot interceptors, amid the ongoing war with Iran.

Officials briefed on the effort described the scale as unprecedented and said the goal extended beyond identifying potential leakers to deterring future disclosures.

The Joint Staff, which supports the chairman of the Joint Chiefs of Staff and coordinates military operations, employs between 1,500 and 2,000 personnel. Not every senior leader underwent testing, including the chairman himself.

Pentagon spokesman Sean Parnell stated that the department takes leaks of classified national security information extremely seriously and investigates them accordingly, while emphasizing the need to secure such information to protect U.S. troops.

The polygraph examinations followed multiple news reports detailing the rapid expenditure of advanced munitions in the Iran conflict. Some sources indicated that no individuals failed the specific questions regarding media disclosures.

This action aligns with prior efforts by Defense Secretary Pete Hegseth to address unauthorized disclosures through stricter measures on personnel with access to sensitive data.