Dan Caldwell, a top adviser to Secretary of Defense Pete Hegseth, was put on leave this week amid an investigation into leaks at the Department of Defense.
Caldwell was escorted out of the Pentagon on Tuesday and placed on administrative leave for “an unauthorized disclosure,” a department official told Reuters. The announcement comes several weeks after the Pentagon launched a probe into leaks of classified information.
“The investigation remains ongoing,” the official said under the condition of anonymity.
On March 21, Hegseth’s chief of staff, Joe Kasper, requested an inquiry into “recent unauthorized disclosures of national security information involving sensitive communications.” The nature of the information Caldwell allegedly disclosed is unknown.
Kasper added that the department would use polygraphs “in the execution of this investigation” and “in accordance with applicable law and policy.” Information “identifying a party responsible for an unauthorized disclosure would be referred for criminal prosecution,” he added.
An Iraq war veteran, Caldwell was formerly a policy adviser at Defense Priorities, an organization that advocates for a “restrained” foreign policy approach. Caldwell has helped advise the Pentagon’s strategy in Ukraine since joining the administration. Caldwell was also one of the 18 people in a national security Signal group chat that discussed operational information and mistakenly included Atlantic editor Jeffrey Goldberg.
In the chat, Hegseth described Caldwell as the Pentagon’s primary contact for conducting military strikes on Yemen.
Concerns over leaks have plagued the Trump administration so far. Homeland Security head Kristi Noem is seeking to expel leakers from DHS with the help of lie-detector tests, she said in early April.
“Under Secretary Noem’s leadership, DHS is unapologetic about its efforts to root out leakers that undermine national security,” DHS Assistant Secretary for Public Affairs Tricia McLaughlin said. “We are agnostic about your standing, tenure, political appointment or status as a career civil servant — we will track down leakers and prosecute them to the fullest extent of the law.”
Director of National Intelligence Tulsi Gabbard has also said that “we know of and are aggressively pursuing recent leakers from within the Intelligence Community and will hold them accountable.”
“Politically motivated leaks undermine our national security and the trust of the American people and will not be tolerated,” Gabbard said in mid-March, pointing to cases in which leakers allegedly released sensitive information to media outlets, including the Washington Post and the Huffington Post. “Unfortunately, such leaks have become commonplace with no investigation or accountability. That ends now.”