The US Senate Select Committee on Intelligence held a hearing today, June 6th 2017, on FISA legislation (LINK: Full hearing video recording). This hearing included testimony by the following witnesses:
Director Daniel R. Coats\ Director of National Intelligence (DNI)
Acting Director Andrew McCabe\ Director of the Federal Bureau of Investigation (FBI)
Admiral Michael S. Rogers\ Director of the National Security Agency (NSA)
Deputy Attorney General Rod J. Rosenstein\ Deputy Attorney General of the Department of Justice (DOJ)
Each witness at several points indicated that they would not or could not respond to direct questions posed by the congressional committee. Examples of this can be particularly seen in Senator Martin Heinrich's time (1:44:46 to 1:50:06) and Senator Angus King's time (1:55:30 to 2:01:55).
Selected excerpts from those two particular sections
Director McCabe: "And I think that those matters also begin to fall within the scope of issues being investigated by the special council, and wouldn't be appropriate for me to comment on those today."
Director Coats: "I do not share with the general public conversations I have with the President or many of my administrative colleagues... that I believe should not be shared."
Senator King: "Why are you not answering these questions? Is there an invocation of executive privilege by the President of the United States? Is there or not?"
Admiral Rogers: "Not that I am aware of."
Senator King: "Then why are you not answering our questions?"
Admiral Rogers: "Because I feel that it is inappropriate, Senator."
Senator King: "What you feel isn't relevant, Admiral..."
Senator King: "I am not satisfied by, 'I do not believe it's appropriate' or 'I do not feel I should answer'. I want to understand a legal basis. You swore that oath to tell us the truth, the whole truth, and nothing but the truth. And today you are refusing to do so. What is the legal basis for your refusal to testify to this committee?"
Director Coats: "I'm not sure I have a legal basis..."
Director Coats and Admiral Rogers both refer to issues regarding the setting of this discussion and possible involvement classified information as reason why they are not able to answer. But this seems like broad authority to not answer a question, without legitimate privilege.
Senator King explicitly closes his questioning period by stating, "It is my belief that you are inappropriately refusing to answer these questions."
What are the legal requirements to answer questions when testifying in this setting?
What is the legal recourse for compelling withheld responses in this setting?
What is the legal authority of the US intelligence community leaders to determine the appropriateness of the questions asked to them?