To complain or lecture loudly and with angry emotion.
Upset about his neighbors load music at 3:00 am, Davis knocked on the door and proceeded to read the riot act. "Reading the riot act" used to be a literal event. Bobbies in Britain used to read a prescribed proclamation, known as the Riot Act, before they could break up or arrest a crowd. The Riot Act is used in a fashion similar to the Miranda Rights in the US. The Bobbies would approach the crowd, read the Riot Act aloud, and then disperse or arrest them.