Riot Act felt uncertain of their power to take action to stop the riots without a reading of the Riot Act. After the riots, Lord Mansfield observed that the Riot Act did not take away the pre-existing power of the authorities to use force to stop a violent riot; it only created the additional offence of failing to disperse after a reading of the Riot Act. The Riot Act was read prior to the Peterloo Massacre of 1819, as well as prior to the Bristol Riots at Queen's Square in 1831. Both are held to be related to the Unreformed House of
Peterloo Massacre Guy L'Estrange. The contents of both notes were similar: The notes were handed to two horsemen who were standing by. The Manchester and Salford Yeomanry were stationed just a short distance away in Portland Street, and so received their note first. They immediately drew their swords and galloped towards St Peter's Field. One trooper, in a frantic attempt to catch up, knocked down a woman in Cooper Street, causing the death of her son when he was thrown from her arms; two-year-old William Fildes was the first casualty of Peterloo. Sixty cavalrymen of the Manchester and Salford Yeomanry, led by