Intel briefing

Intelligence briefings become flashpoint for Trump and Clinton campaigns

It is unclear exactly how many members of the campaigns receive the briefings; the presidential and vice presidential nominee receive the briefings without requiring separate security clearances, while aides must have clearance to accompany, according to an intelligence official.

Max Stier, president of the Partnership for Public Service — which runs the Center for Presidential Transition — said that the complexity and the importance of the transition process means it must begin now, particularly when it comes to national security.

"Whoever wins, we should want a president that's well-prepared to run our government," Stier said. "The briefings are a small piece of a larger action that's necessary here."