can a business card be left (betw) the mailbox and flag?

[Matt Berklacy]

hi, just wondering, (for hard concrete facts)..if you have any link addressing this, ...specifically..

..can a business card, or note, be left (betw) the mailbox and flag?

employees give mixed opinions (alot).

one supervisor said they own the whole box, but someone owns a house and i get political flyers left on the door step alot and church things..

thx, 

(p.s., this question does not ask about placing Inside a mailbox, thats already known, or the default opinion: no, .....lol...)