Attorney General Merrick Garland on Friday announced new restraints on the U.S. Justice Department’s use of the state secrets privilege to block the disclosure of information in litigation that could harm national security.

In a memo to heads of all executive agencies and DOJ divisions, Garland said he will require the leaders of all executive departments or agencies seeking to invoke the state secrets privilege in litigation to personally submit a request to the Justice Department along with a declaration from the agency head outlining why the privilege is necessary to protect national security. If the department head has limited personal information on the matter, an agency expert must provide a more detailed declaration.