The Gordon Riots of June 1780 were the most destructive civil unrest in London's history, sparked by the Papists Act of 1778 which lifted long-standing legal penalties on Roman Catholics. Lord George Gordon, president of the Protestant Association, led a massive petition march of 50,000 people to Parliament. What began as a peaceful protest rapidly deteriorated into a week of unchecked rioting, arson, prison breaks, and attacks on public institutions, leaving over 280 people dead.
Gordon himself did not participate in the violence, but the British Crown held him personally responsible for inciting the chaos and charged him with high treason under the Treason Act of 1351. The prosecution relied heavily on the doctrine of constructive treason—a controversial legal theory where an act not explicitly treasonous in intention is interpreted as levying war against the King due to its catastrophic public consequences. During Gordon's famous 1781 trial, his defense attorney, Thomas Erskine, delivered a brilliant closing argument that dismantled the Crown's argument.
Erskine contended that treason required a clear, deliberate intention to overthrow the sovereign, not merely leading a passionate public assembly that spun out of control. The jury acquitted Gordon, delivering a massive blow to the Crown's reliance on constructive treason. This landmark verdict set a vital legal precedent in Anglo-American jurisprudence.