Invite is not the key word. Congress has no reason to kiss Roberts ass. Congress created FISA courts and placed Roberts in charge of them. Congress can completely abolish the FISA court in an afternoon if it doesn’t like how Roberts runs them. And Roberts cannot do a thing about it.
So really, Roberts needs to show a little respect and provide some answers to the Congress that oversees, creates, abolishes, and funds all federal courts.
Congress may do anything it wants to all federal courts and judges, except it may not abolish the Supreme court. That’s about it.
I agree, unfortunately the House and the Senate is gutless to do anything with regard to FISA.