Holidays September 17, 2024 4:23 pm What is Constitution Day? Constitution day is a federal holiday that commemorates the signing of the U.S. Constitution in 1787. US & World Videos 1:07 Los Angeles authorities reviewing possible resentencing for Menendez brothers 1:07 US dockworkers agree to tentative deal, ending strike 1:08 3 officers convicted in Tyre Nichols fatal beating 1:59 Death toll increases in Lebanon as Israel expands aerial and ground offensive 1:49 Eminem reacts to daughter Hailie Jade's pregnancy