Flags at half-staff for Bush: What are the guidelines and precedents to follow?

President Donald Trump is directing that American flags be flown at half-staff for 30 days to honor the memory of former President George H.W. Bush.

In a proclamation signed Saturday hours after Bush died, Trump is also designating Wednesday as a national day of mourning. Trump encourages Americans to gather in places of worship "to pay homage" to Bush's memory.

When must a flag be lowered to half-staff? Though precedent is often followed, there are also guidelines outlined by President Dwight D. Eisenhower in a 1954 proclamation. Aside from the instances outlined by Eisenhower, the president can also choose to lower a flag whenever the nation is mourning, whether it is after a tragedy or after the death of another official not outlined in the proclamation.

If the flag at the White House is raised, the rest of the country is not required to follow the president's lead, according to the Official Guide to Government Information and Services. For instance, a school may choose to lower all of its flags to half-staff after the death of a student.

Here are all of the guidelines about how long to leave flags at half-staff, set out in Eisenhower's proclamation.

• President or former president's death: 30 days


• Vice president, the chief justice or a retired chief justice of the United States Supreme Court, or the speaker of the House of Representatives: 10 days



• Associate justice of the Supreme Court, a member of the Cabinet, a former vice president, the president pro tempore of the Senate, the majority leader of the Senate, the minority leader of the Senate, the majority leader of the House of Representatives, or the minority leader of the House of Representatives: Death until interment


• United States senator, representative, territorial delegate, or the resident commissioner from the Commonwealth of Puerto Rico: On the day of death and the day after


• The governor of a state, territory or possession: Day of death until interment

The Associated Press and ABC News contributed to this report.