People still get trials. They still get due process. If the DEA/FBI can't provide evidence to the state/federal prosecutor such that a person is found guilty of a crime by a jury of his peers, then a person does not get convicted.

You're saying the government is committing thought-crime. Just because a person owns a gun doesn't mean they're going to kill their neighbor, and just because the FBI/CIA/NSA/Local PD "could" abuse its power, does not mean they "do".