The idea of a Peace Officers Memorial Day came into effect on October 1, 1961, when Congress asked the president to designate May 15 to honor law enforcement officers. President John F Kennedy signed the bill into law on October 1, 1962. Each year, the president of the United States proclaims May 15 as Peace Officers Memorial Day and the calendar week of each year during which such May 15 occurs as Police Week.
According to the Legal Information Institute, the president is requested to issue a proclamation to: designate May 15 as Peace Officers Memorial Day; to direct government officials to display the United States flag at half staff on all government buildings; and to invite state and local governments and the people to observe the day with appropriate ceremonies and activities.