Go back and look at the picture. Hardly something you can put in your purse, so that leaves it to groups with authority and no fashion sense.
There is potential for great abuse, like preventing citizens from exercising their right of peaceful assembly (read protesting) .....without them even knowing who is doing it.
This thing is here, it's not going to be uninvented. But it's a worrisome weapon, because it can be used illegally with no evidence that would be needed to to take anyone to task for violating your rights.
