Pressure Point Control Tactics (PPCT) is the use of pressure points in a law enforcement capacity. By pressure points, I am not referring to Chinese meridians, rather nerve clusters that are accessible unarmed or with an impact weapon (e.g. ASP, PR-24). I took a PPCT class about 14 years ago. I am not law enforcement, but I was a martial arts student of the civilian instructor who was certified to teach it, so some of his martial arts students took the class along with local LEO. As I was the largest person in the class, I was also the demonstration dummy for these techniques.
We learned several points, but the only two I still remember were the "C clamp" maneuver and a thigh strike that hits the same nerve that Thai Boxers aim for in their leg clips. The C-clamp was interesting because (according to the instructor) it was a good method to get a non-compliant, yet non-violent, person to move where you wanted them to go. The best way I can explain it is that you are using one hand to apply pressure on 2 or three separate pressure points, behind the ear, under the nose, and the upper lift.
He mentioned peaceful public protests situations as an example of where they could be used. For example if people are sitting in front of a building, blocking the entrance. Trying to pick up someone who is acting as dead weight can be very difficult. On the other hand, you can't just pull out your baton and beat the hell out of a bunch of peaceful demonstrators in front of the camera. Using the "C clamp" causes enough pain to force the protester to comply quickly with your commands, but does not injure them.