The employee handbook is a contract. A contract could be amended, and still be lawful, if you follow the correct steps. I'm just speaking out of my posterior here, but most companies require you to sign a statement that gives your acknowledgment to the corporate policies. If you were to amend your handbook, and indicate on the statement that you sign that you amended it, then if your employer overlooks it, doesn't catch it, but you still made some effort to point out to them that you did change your copy of the handbook, then in my amateur-legal-mind, they would have little recourse if you did have a firearm in your vehicle.
When the office I work for was revising their handbooks, and the subject came up about weapons, I offered a suggestion for the wording. They did wind up changing it from "employees shall not possess any weapons while on company property blah blah blah" to "employees shall not possess any Illegal weapons on company property blah blah blah".
Hey, its not my fault they couldnt understand what difference that one word made to their policy.
"No, this pistol is not an illegal weapon, its 100% lawful."
