My agency has a policy that basically says that if you want to carry off-duty on their creds then you must comply with applicable agency policy, carry the pistols you're authorized to, loaded with the ammunition you are issued, and in a holster that meets their minimum guidelines. (Most quality concealment holsters; if they are deamed good enough for plain clothes work, they are good enough for off-duty use.)
If you don't want to carry off duty on their creds, then you must comply with applicable state laws, carry personally owned guns not authorized for work, load them with personally purchased ammunition, in whatever manner you want.
Most folks carry on their creds unless they percieve a specific benefit, such as concealing trail guns, wanting to carry a personally owned weapon for whatever reason, or wanting to avoid policy mandates concerning drinking and carrying; forbidden by policy, but allowable in some states. Things like that.
Well, conversely, for Feds (and perhaps for other LEOs as well...I forget...), the Federal Tort Claims Act is supposed to protect you from personal liability if you're within the scope of your duties when you take an action. Acting to stop a crime of violence or an attempted crime of violence is specified as within the scope of one's duties in the statute, soooo... you should be OK. But there still may be a fight about exactly who is supposed to stand in your stead in an ensuing lawsuit. If you're not carrying on your agency's creds or authority, they may try to pawn it off on someone else (and you should probably be looking for another employer with some backbone, but that's another story...)
Originally Posted by 64zebra
Certainly, it's better to worry about that than to say, "Wow, maybe I should have acted quicker to try and save that person's life."