TexasCHLforum.com

Land occupier rules require an occupier of land to protect business invitees, and even trespassers in some states, from dangerous conditions and require the land occupier to inspect and correct discoverable dangerous conditions. This is whst is behind the "clean up on aisle 3" calls. There is an entire industry centered around slip and fall injuries in retail stores.

There are some causation issues, because merely having a weapon will not prevent one from injury, as seen by the stories of armed folk who are injured or killed for their self defense efforts.