Read the Riot ActThe phrase's surprisingly literal and deadly origins.

From the show

History of Phrases

The expression for a stern scolding has a much more serious history. Discover the British law from 1714 that gave rise to this common idiom. The Riot Act required an official to read a proclamation to an unlawful assembly. If the crowd didn't disperse within an hour, the consequences could be fatal. This legal warning evolved from a life-or-death ultimatum into the metaphor we use today.