The idea is to discourage the authorities from acting unlawfully because as soon as they get free reign to do so how can you ever be sure of a person's guilt?

The idea is to discourage the authorities from acting unlawfully because as soon as they get free reign to do so how can you ever be sure of a person's guilt? Considering how advance technology is there are already reasons to doubt any system which is not fully encrypted beyond the government's access of not having had evidence planted or manipulated.