I wrote this a few years ago for IBAT after the open carry law was passed (I edited it a bit). Now, we have constitutional carry.
Most banks are not going to be interested in making it a crime for a customer to carry a gun on the bank’s premises—whether concealed or open. So, why would you bother with the statutory sign, which will take up the better part of an entire glass entrance door to your building. A better bet might be to post a nonconforming sign and provide your officers with cards with the statutory language printed on them. Why? Because, when you hand the card to someone who is carrying a gun on bank property premises and they refuse to leave, then it becomes a crime—regardless of what sign you post or whether you post a sign at all. That way, if someone enters the premises who you think (or know) is ignoring your signs and is carrying a gun in the bank, you can hand them the card and then it becomes a crime if they continue to carry on the premises. This is particularly helpful if someone you think is carrying a gun is threatening or yelling at your staff.
One option with regard to nonconforming signs is to post something that expresses the bank’s support of the right to carry and/or the 2nd Amendment, but also asks folks to not bring their guns into the bank. Or you can just post the typical red circle with a line through a handgun and long gun.
Banks are taking a variety of approaches.
If someone comes into your bank armed and with ill intent, the violation of the statutory sign is the last of your concerns. Don't worry, there are other crimes they can be prosecuted for. And you can communicate that you don't want weapons on premises and make it a crime for someone to remain on your premises with a weapon without these huge signs. I think the statutory signs are unsightly and could obscure the view that bankers want out their doors for safety.
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