House committees conducting impeachment proceedings can't force officials from executive branch agencies to testify about matters that might involve protected information without government lawyers present, the Justice Department said in a new legal opinion.
"Congressional subpoenas that purport to require executive branch witnesses to appear without agency counsel in these circumstances are legally invalid and are not subject to civil or criminal enforcement," according to the Nov. 1 opinion released Monday by the department's Office of Legal Counsel.
The opinion is the latest obstacle to efforts by the House Intelligence Committee and other panels to require testimony from White House officials in the impeachment investigation against President Donald Trump. House Intelligence Chairman Adam Schiff, a Democrat, has said that such obstacles will in themselves be taken as evidence that the administration is obstructing justice.