She's smart by putting this out there now. Even if they detain her for some unknown reason, she can still contact her attorney, who then alerts the local and national media and now the FBI have a firestorm of publicity they don't want. Along with several lawsuits I'm sure her attorney would file immediately.
Sure, they can do that, but the repercussions are something they certainly don't want to deal with.
What if it turns out that most of these agencies don't care about negative publicity (because they can't be fired) or lawsuits (because it's not their money)? That's the part that really scares me: no transparency, no accountability, and a bunch of secretive True Believers running things. Like the Chinese government!
Sure, they can do that, but the repercussions are something they certainly don't want to deal with.