The letter from Sen Grassley and Johnson is a red herring. Going after the FBI in this manner is useless. Their response will be that they were in an ongoing investigation and doing their job.
AG Barr needs to respond to this letter that there is an ongoing investigation and he will not respond.
AG Barr said before he is investigating the predicate of the surveillance. The predicate is what will slowing turn the blowtouch in the direction of the perps for spying.
And furthermore, investigations have already been going on for many months/over a year. Huber.