We aren't talking about 'law' here, we're talking about 'people.' That gets lost some times.
Someone with access to these tools might decide the shake down Jack with a bit of blackmail. They might decide to sell union organizing 'alerts' to business. These are not legal but there are many people who work in an organization with these tools available who could justify abusing them.
Consider another hotbed subject which gets argued the other way all the time, gun ownership.
Now we can all agree that someone owning a gun who follows all of the safety precautions, and doesn't wave it about irresponsibly Etc is no threat to society. And yet the argument is put forward that the capability is the threat and people other than the owner may exploit that capability (a thief steals the gun, a spouse grabs it in a fit of rage, Etc.) and that it is "better" to not allow the person to own a gun because the risk of that gun falling into the wrong hands and doing something bad are non-zero enough.
This is the same argument we should make on surveillance technology, which is that the potential for its abuse and damaging the lives of innocent civilians, out weighs the 'benefit' the law enforcement agency gets from having it. There are other ways for the agency to do its job, just as there are other ways for our homeowner to protect their property, that don't require this capability.