In what movie is all criminal activity, including murder legal for 12 hours?

"The Purge" is an American anthology media franchise centered on a series of dystopian action horror films distributed by Universal Pictures and produced by Blumhouse Production and Platinum Dunes, which are written and in some cases also directed by James DeMonaco.

The films present a seemingly normal, crime-free America in the near-future. But the truth is that the country is a dystopia which celebrates an annual national holiday known as "the Purge", a day in which all crime, including murder, becomes decriminalized for a 12-hour period. DeMonaco wrote the screenplays for all films in the series. A fifth instalment, The Forever Purge, was released on July 2, 2021.

In the films, the franchise following an economic collapse and rising social unrest, a political organization named The New Founding Fathers of America (NFFA) is formed and is voted into office. The organization establishes a new totalitarian government and a police state. In 2016, the NFFA devises a plan to help stabilize American society and later in 2017, the 28th Amendment to the U.S Constitution is ratified. This amendment establishes a 12-hour event known as "The Purge" which would take place from 7 PM on March 21 to 7 AM on March 22 wherein all crime becomes legal. Before the Purge begins, the Emergency Broadcast System is activated with rules and a prayer saying "Blessed be our New Founding Fathers and America, a nation reborn" before ending with "May God be with you all".