I don't think that the relationship is that straightforward.
You can, absolutely, build bureaucracies to resist accountability and avoid transparency; where nothing is every anyone's fault in particular, and all the records are classified, and the department in charge of checking its own work invariably concludes that procedure was followed. It takes some doing because the amount of formalized process required to keep a large org from just disintegrating means that you can't help but leave a paper trail, meeting minutes, policy documents, etc. that all need to be sanitized or kept out of reach of discovery and meddling reporters; but is certainly doable, especially if you can apply steady pressure over a prolonged period of time.
The high-cohesion/small-size case, though, tends to degrade into the 'if the mayor, the sheriff, and the DA get along they can basically do whatever; if the sheriff is prickly enough they might not even need the DA' awfully quickly and easily. Crumbles more quickly if there's a falling out internally or something Bad happens that has FBI agents sniffing around, since there's no entrenched apparatus designed to create the impression that organizational norms are being upheld; but, if that doesn't happen, it can be very opaque since it's small enough that no formal management and only very limited recordkeeping are required; and accountability is effectively nonexistent.