The lawsuit by the New York Times in Washington DC federal court alleged that policy changes by the Defence Department in 2025 gave it free rein to freeze out reporters and news outlets over coverage the department did not like, in violation of the Constitution's protections for free speech and due process.
The government disputed that characterisation and said the policy is reasonable and necessary for national security.
US District Judge Paul Friedman said in his ruling on Friday that he recognised the importance of protecting troops and war plans but that it was "more important than ever that the public have access to information from a variety of perspectives about what its government is doing" in light of President Donald Trump's recent "incursion" into Venezuela and war with Iran.
The Pentagon and the New York Times did not immediately respond to requests for comment on the ruling. The government is likely to appeal.
The changes approved under Defence Secretary Pete Hegseth in October state that journalists can be deemed security risks and have their press badges revoked if they solicit unauthorised military personnel to disclose classified, and in some cases unclassified, information.
Of the 56 news outlets in the Pentagon Press Association, only one agreed to sign an acknowledgement of the new policy, according to the Times' lawsuit. Reporters who did not sign surrendered their press passes.
The Pentagon assembled a new press corps consisting of pro-Trump outlets and media personalities after the exodus of reporters, which the Times said was evidence that the policy was aimed at stifling unflattering coverage.
The policy states that publishing sensitive information "is generally protected by the First Amendment" but says soliciting that information could be considered by officials when determining whether a reporter poses a "security or safety risk".
In its lawsuit, the Times said the policy unlawfully restricts essential news gathering techniques and gives the Pentagon "unfettered" discretion to revoke passes, permitting it to impose the type of "viewpoint-based" press restrictions forbidden by the Constitution.
Justice Department lawyers acknowledged the policy was partly subjective but said press credentialing decisions were still governed by neutral, objective criteria. The government also said soliciting military personnel to commit a crime by disclosing unauthorised information was not legally protected speech.
The policy change was criticised by journalism advocates, who called it another attack on the free press by Trump and his administration.
