Here is a post I recently read by a Denver Lawyer who wishes to remain anonymous :
The posturing of advocates for immunity notwithstanding, whether the administration's requests were in violation of the applicable laws was not a close question. Although this has largely been flushed down the memory hole, Qwest refused to cooperate with the government and demanded that proper legal procedures be followed before it would proceed. Qwest's attorneys did not think that the government's proposed course of action was even arguably within the scope of the law. AT&T and Verizon (whose combined revenues last year were approximately $150 billion) could easily have consulted with qualified counsel and determined the same thing. Contrary to the breathless hysteria about cooperating with the government in "emergencies," the program at issue was developed over several months and operated for multiple years, requiring the involvement of hundreds, if not thousands, of people. It was not the situation of a police officer running up to an individual on the street and saying that he or she must do something NOW with no opportunity for reflection or consultation.
I should also add that I primarily do defense work and therefore am generally sympathetic to allegations of meritless claims, over the top punitive damage awards, etc. However, there is a very fundamental problem with any party getting a law changed to retroactively immunize it for unlawful conduct that it has all but confessed to. When the parties seeking immunity are multi-billion dollar corporations that have donated lavishly to members of Congress, it becomes even more troubling and damaging to people's confidence in the justice system. Indeed, there's a term for countries in which the wealthy can purchase immunity for themselves: "banana republic".
He pretty well sums up the situation from a legal point of view.
To compleat your metaphor neue, there is no need to go on a fishing expedition when the "fish" have already jumped in the boat trying to convince you that they should not be caught.