A senior advisor to Defense Secretary Pete Hegseth was escorted out of the Pentagon on Tuesday and placed on administrative leave, according to a Defense Department official.
Reuters first reported that Dan Caldwell was suspended over an “unauthorized disclosure” of information, amid an ongoing investigation into leaks from within the Pentagon. A DOD official confirmed the report to Fox News Digital but declined to comment further due to the active investigation.
Caldwell, a foreign policy realist, previously worked with the restraint-oriented think tank Defense Priorities and Concerned Veterans for America, which was formerly led by Hegseth. He has been a vocal advocate for significantly reducing the U.S. military presence in Europe and withdrawing troops from Iraq and Syria.
In March, the Pentagon announced an effort to identify leakers from within the Defense Department regarding “recent unauthorized disclosures of national security information.” The announcement said that the DoD would use polygraph exams to identify who was allegedly leaking sensitive or secret data, Fox News noted.
“The use of polygraphs in the execution of this investigation will be in accordance with applicable law and policy,” DOD Chief of Staff Joe Kasper wrote in a memo. “This investigation will commence immediately and culminate in a report to the Secretary of Defense.”
“The report will include a complete record of unauthorized disclosures within the Department of Defense and recommendations to improve such efforts,” the memo said.
The memo also noted that “information identifying a party responsible for an unauthorized disclosure” would be referred for criminal prosecution.
Caldwell’s close ties to Hegseth were highlighted in a leaked Signal chat about U.S. strikes on the Houthis, in which Hegseth identified him as the Pentagon’s point of contact for the operation. The private conversation was exposed after National Security Advisor Mike Waltz accidentally added The Atlantic editor-in-chief Jeffrey Goldberg to the group.
The Defense Department is the latest federal entity to announce the use of polygraphs to identify potential leakers, following similar moves by the Departments of Homeland Security and Justice. The DOD directive came shortly after President Donald Trump dismissed a New York Times report claiming that Department of Government Efficiency head Elon Musk would be briefed on “war plans” with China during a Pentagon visit.
Trump firmly denied the claim, stating he would not share such plans “with anybody.”
At this time, there is no evidence linking Dan Caldwell to that particular leak, and the nature of the unauthorized information he may have disclosed remains unclear, Fox noted.
Following the Times report, Hegseth’s chief of staff, Kasper called for an investigation, which he said would include the use of polygraphs, into “unauthorized disclosures” of national security information, according to Bloomberg.
Kasper also said he wanted the leakers to “be referred to the appropriate criminal law enforcement entity for criminal prosecution.”
Musk also pushed back on the Times report on his X platform.
“The New York Times is pure propaganda. Also, I look forward to the prosecutions of those at the Pentagon who are leaking maliciously false information to NYT. They will be found,” he wrote in a post containing a screenshot of Trump’s Truth Social post.
Homeland Security Secretary Kristi Noem also noted in a video posted on social media last month that she used lie detectors to learn who was leaking sensitive information to the media.
Her investigation “identified two leakers of information here at the Department of Homeland Security who have been telling individuals about our operations and putting law enforcement lives in jeopardy. We plan to prosecute these two individuals and hold them accountable for what they’ve done,” she said.
“We’re going to continue to do all that we can to keep America safe,” she added.