Not to mention eventually someone is going to figure out how to get a drone to understand sign language. The only way I can think to jam a drone's camera from reading sign language is going to be shining a bunch of lasers at anything that looks like a camera (probably using your own counter drones). Or someone is going to figure out how to take videogame AI and jam it into a drone.

Even if we somehow restrict criminals from getting drone AI (which is on it's face reasonable ... most AI experts probably don't want their work falling into the hands of criminals building kill bots), then I doubt we'll be willing to restrict people from owning half-life because it turns out its AI makes a good autonomous FBI obstructing bot.