When the Simon Commission visited Lahore on 30 October 1928, Lala Lajpat Rai led a peaceful protest against the Commission. The police responded with violence, with the superintendent of police, James A. Scott, ordering his men to "lathi" charge the protesters. Lala Lajpat Rai was beaten but addressed a meeting later. He died on 17 November 1928, perhaps in part because of his injuries although this is uncertain. Historian Neeti Nair says "His death was widely attributed to the mental if not physical shock he had suffered." When the matter of Rai's death was raised in the British Parliament, the government denied any casual role. Although Singh did not witness the event, he vowed to take revenge, and joined other revolutionaries, Shivaram Rajguru, Sukhdev Thapar and Chandrashekhar Azad, in a plot to kill Scott. However, in a case of mistaken identity, Singh was signalled to shoot on the appearance of John P. Saunders, an Assistant Superintendent of Police. He was shot by Rajguru and Singh while leaving the District Police Headquarters in Lahore on 17 December 1928. Chanan Singh, a Head Constable who was chasing them, was fatally injured by Azad's covering fire.