Probably the law of unintended consequences. Imagine now that this makes the surveillance of the bureaucracy itself more or less infallible. Someone, or many people, now know which party officials are meeting with which, know who their mistresses are, know the places they are going to hide assets or crimes, know the people bribing them. Now you have a roadmap for corruption of the state.

If that data leaks, is hacked by a state actor and released, or becomes the tool by which bureaucrats seek to manipulate and blackmail each other, it could destabilize the party itself.