cia. for the most part, it's mission is devoted to targeting america's actual foreign enemies and by law they can't directly collect on americans. it is much much harder for politicians to suborn the cia through appointments and hiring practices. meanwhile the fbi is much much more vulnerable to those and is in effect much much more suitable towards targeting domestic political dissidents. cia can have siloed resident agencies that can pretty much do awful things because everything is compartmentalized of course, but by structure the fbi is always the go to for being used as a tool of oppression.
Switzerland