When your badge breaks, it's bad. Be it by gunfight, or by an unnamed bounty hunter saying, "Think you people need a new sheriff." right before taking your badge. Situations like this haunt all men and women of justice, because without your badge, you can't command respect. That badge may be all that stands between you and a Colt Revolver.
My badge recently had the clip break off, thanks to it being cheap and not hand-forged in the Arizona Territory. Hopefully, with this Instructable, you can prevent the same thing from compromising you protecting law and order.
Step 1: Preparation
To begin with, I got the materials needed, which should be on hand. All I needed was a safety pin a little bit shorter than the star was wide, and some epoxy* to hold it down. I was a little worried about epoxy at first, but it dries incredibly hard, and in copius quantities, is even better than the original fastener. Also, since you're using a safety pin the badge will stay on more securely, s definite plus after bumpy miles on horseback.
Rub some sandpaper on the back of the badge to rough it up, and provide a better surface for the epoxy to stick to. Test out some possible locations of the safety pin, and find one that works right for your badge, You'll want to have a little space between the pin and the edge.
*Prettier alternatives: solder, though I'm not sure how secure it would be, and welding.