And sieze the drives, thumb drives, and freeze the e-mail accounts of those concerned to prevent deletion of data. Either that or have a pipeline out of the NSA with all the data.
Nothing crashes a hard drive faster than a Congressional Subpoena.
All Federal employees take an oath that is VERY similar to one take by enlisted and officer members of the US military. Here it is:
I, ______________, do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion; and that I will well and faithfully discharge the duties of the office on which I am about to enter. So help me God.
Congress should declare, openly, that we are at a crisis in government due to Executive branch lawlessness. It should call on all Federal law enforcement officers (including the FBI and the US Marshalls) to adhere to their oaths. Any Federal officer who is found to be in collusion with, or involved in the suppression, of the truth and existing law will have their Federal pensions, Thrift Savings Accounts, and Federal Employee Health Benefits forfeited.