Open carry in walmart

friday’s (09/21/19) show open carry
does this “no open open carry” apply to the police? the police open carry a number of weapons openly …

additionally when Nobody was banned from the jail (no trespass order), does that mean the cops cant take him there should they try to arrest them.

cop: your under arrest for and we will be taking you to jail
nobody: you cant take me there, the jail has a no trespass order against me, so i cannot go there.