In July 2014, Ellis was successful in calling for the Parliamentary authorities to officially mark the assassination of a former Member of Parliament for Northampton, Spencer Perceval, who had become Prime Minister, and who was shot and killed in the House of Commons in 1812. The Parliamentary authorities agreed to install a brass plaque in St Stephen's Hall commemorating the notable assassination and Ellis called this a "fitting tribute" to the former Prime Minister and historic Northampton figure.