Today my uncle called me and asked if i would help him distribute fliers for his small bussniess. I said sure, he said as long as i did not put the flairs in the mail box, or on any moving parts i would be good. I have found a way to fold them and stick them between a brace on the mail box in a opening, after i did a few like this the mailman stopped me and said it was a federal offence to put objects on a mail box, i told my uncle this and he said only the inside of the mail box is technically government property. Where would i look this up? and if you know please tell me?

PS. if your gona say TL;DR just dont even post.