Interpreting the individual freedoms in the bill of rights is the task of ?

The supreme court, they interpret how the constitution applies and how it should be enforced when they make rulings.

An informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.