Responding to a resurgence in socialist and other radical activity in London, and clashes at a massive demonstration earlier that year, the new Metropolitan Police commissioner, the former colonial governor Sir Charles Warren, had banned all meetings in Trafalgar Square. He determined to enforce the ban with the utmost ferocity.
One of the many demonstrators arrested was the Radical MP for Lanark, Cunningharn Grahame. A neutral bystander described what happened: 'After Mr Grahame's arrest was complete one policeman after another, two certainly, but I think no more, stepped up from behind and struck him on the head from behind with a violence and brutality which were shocking to behold. Even after this, and when some some five or six other police were dragging him into the square, another from behind seized him most needlessly by the hair ... and dragged his head back, and in that condition he was forced many yards.'