An organization flies the US Flag, along with those of the State and the Corporate "flag" 24 hours a day, 7 days a week with appropriate lighting as proscribed. During a period of mourning as directed by Presidential Proclamation the Flag is to be flown at half-staff for the period indicated in the Proclamation. What I cannot find anywhere s specific guidance for the period from Sunset to Sunrise. If the Flag is flown 24 hours a day is it to be flown at Half-staff during the hours of darkness? Is it raised during the hours of darkness? I can find information concerning almost every aspect of this except for this question. My purely personal view is if the US Flag is flown day and night it is to be at half-staff for the entire 24 hour period.