text: what are the rules of hanging the american flag? i do know that your not suppose to have the flag touch the ground,but i always thought the flag was suppose to be brought in at night and not displayed out in the rain. the flags rules change as flag material and other rules change.  a flag as long as it is made of water proof materical may be left flying in the rain.  a flag on display with a dedicated light can be left out 24 hours a day  you can see most of the current laws at  http://www.ushistory.org/betsy/flagetiq.html