<P> Federal law includes a Congressional request that the flag be flown at half - staff on Peace Officers Memorial Day (May 15), unless that day is also Armed Forces Day . Presidential proclamations also call for the flag to be flown at half - staff on Pearl Harbor Remembrance Day (December 7), and Patriot Day (September 11). </P> <P> On October 16, 2001, President George W. Bush approved legislation requiring the United States flag to be lowered to half - staff on all Federal buildings to memorialize fallen firefighters . Pub. L. 107--51 requires this action to occur annually in conjunction with observance of the National Fallen Firefighters Memorial Service . The date of the National Fallen Firefighters Memorial Service is traditionally the first Sunday in October . It is held at the National Fallen Firefighters Memorial in Emmitsburg, Maryland . </P> <P> 4 U.S.C. § 7 (m) was modified with new legislation signed into effect on June 29, 2007, by President Bush, requiring any federal facility within a region, which proclaims half - staff to honor a member of the U.S. Armed Forces who died on active duty, to follow the half - staff proclamation . </P> <P> Apart from the lowered position of the flag of Vietnam, state mourning also warrants a black ribbon 1 / 10 the width of the flag's width and equal to the length of the flag to be tied at the summit . Variants have the black ribbon wrapped around the flag itself, preventing it from being unfurled . </P>

When can us flag be flown at half-staff