Lingo
[read] {sb} the riot act
to angrily warn or threaten someone so that they will not make the same mistake
The idiom "read someone the riot act" traces its origin to a British legal statute known as the Riot Act of 1715. This legislation granted authorities the power to disperse a gathering of 12 or more people unlawfully assembled, demanding that they disperse within an hour. Before taking further action, a proclamation, known as "reading the riot act," was read aloud to the crowd. The idiom has since evolved to signify delivering a stern warning, reprimand, or expression of disapproval to someone for their behavior.
1 / 1