In most of my nearly 34 years of big-city policing, my badge stayed at home, or otherwise securely locked-up, unless I was wearing the uniform. In my earliest days, I did carry the badge in a wallet made to accommodate it, but soon abandoned that idea. Why? Well, I soon learned that the badge did not impress anyone, unless it was on my uniform.
I cannot think of one truly tactically-valid reason to have a badge, unless there is an easily-recognizable OFFICIAL public servant ID with it.
While I was LEO-ing, if I encountered an armed person, I was not interesting in seeing a badge. I was interested in seeing an official ID, or a license to carry a handgun, and that was only after the situation was under control. Fake, generic, and wannabe badges are for sale at places from souvenir shops to evil-bay. Real police badges can be readily found on the collector market.
Obviously, I recommend against private citizens carrying unofficial badges.
