I am a Police Officer in MA and I have seen many Police Departments in my state training in Aikido. I think this is because of not only its effectivness, but also that it is not perceived by the public as too excessive. In Police work we can not go up and round house kick someone in the head and we can not GNP them into the pavement. That is when the video tapes pop up, your PD is in a law suit and your out of a job.
I am also a member of a 120 Police Officer, Regional Response Team (RRT) that is responsible for covering crowd control and missing persons and I am also on that same Regional teams SWAT team made up of 30 Officers. We cover 50 towns in MA and have worked such events as the DNC in Boston and also the World Series (we were called in after the paintball incident).
I have been training in Aikido for 1 1/2 years and have used it effectivley many times. The RRT team and SWAT team I am on are all also being trained in Aikido by Sensei Jason Delucia. He teaches disarming techniques, take downs, wrist locks etc. all that has been proven very effective to both the 120 Officer RRT team and the 30 Officer Swat team.
If you are intersted you can even view some video footage of the Aikido Police training at his web site www.Aikidog.com
. All the Officers are pleased to have this training because they now it helps keep them safe and out of the court rooms. I ordered a 5 viedeo set of Combat Aikido he sells in "Grappling Magazine" but I think you can also view that on his web site as well.