I started training before I was hired as an officer.....
I have been training in the martial arts for 16 years. Started out with Karate, then Tae Kwon Do, then did some Aikido (Aikikai). After doing that for several years decided to make a move to Judo then to Jeet Kune Do. I never found anything that was serious in my mind, until I started in Tenshin Aikido and then I devoted myself to it.
As far as academy training or post academy training, well, we did the defensive tactics stuff, but I laughed it off as something I would never use. I see a suspect get out of hand and then you have 5 officers jump on him. Why would I even want it to get to that point. I can say that I have always used a technique before the situation has gotten too far and I have difuesed it before other officers would even have to "jump" on the person.
I think it is funny though, because I tend to disagree with our department defensive tactics instructor relating to moves and techniques. He seems to think strength and brutality, while I think simple effective moves (such as Yubi Dori) or a joint lock works better.
They teach arm bars and goose necks, but I have yet to experience soeone combative where those are just the perfect thing to use.
Anyway, I rambled on enough. I would suggest that anyone with the means, find a Tenshin Aikido Dojo in your area and check it out. It is a very effective form of Aikido.