Can you be incriminated for eliminating a public threat in a gun-free zone?

Inb4 "ask a lawyer" and "varies on jurisdiction", but what is the general consensus on using a CCW for self-defense in a designated gun free zone?Scenario: While in a department store with a Gun Free Zone sticker, a gunman walks in and holds up the cashier. In response, you present your firearm and eliminate the threat.In the eyes of the law, would you generally be charged for a misdemeanor/felony even though you probably saved lives? If you want a specific state, I'm from Illinois where gun laws are pretty trash. via /r/CCW http://ift.tt/2vZTfXt