Well, at least the Japanese seem to have a solution in mind....
http://www.nbcnews.com/tech/tech-news/tokyo-police-deploy-net-carrying-drone-catch-rogue-drones-n478596I could not even make this up if I tried. Too funny. Anyone remember those Reeses commercials 'You got peanut butter on my chocolate!'? Well, this is like that except it is 'Hey, you got my drone caught with your drone!'.
Now the 'evil drone users' are gonna' have to come with anti- drone drones. And then the police will come up with anti- drone drone detectors.... which will of course be attached to their drone catching drones.
Brian