I don't believe that most cops out there actually have an intent to do evil, or to trample your rights though. They deal with criminal after criminal after criminal, I think their perspective is more likely that these tools and methods help solve cases quicker and there-for save taxpayer money and that us civilians aren't able to see that perspective.
I think that they aren't aware of the long term implications of what they're doing and that they should stop, but also that it's important not to think of them as evil if you want to have a dialogue with them about change.
There's no nothing wrong with starting a dialogue with "hey! this thing you are doing is wrong!" and I will continue to do so. I try not to judge too harshly on just that though. I hold back the anger in reserve to see how they react once it starts coming to light. Covering up the existence of potential wrongdoing, keep in mind the courts could likely say the tactic is legal, does not bode well for appearances.
I don't care how valuable it is. If it is used by government agencies in a manner that breaks the law, wait, numerous laws and rights, then that implies those agencies feel they are above the law. Once such agencies that enforce the law are no longer beholden to it, things tend to fall apart.