The Treason Felony Act 1848 was enacted during a period of widespread revolutionary fervor across Europe. Designed to target Irish nationalists and Chartists without resorting to the capital punishment associated with high treason, the law created a new category of offense: treason felony. Section 3 of the Act explicitly states that anyone who shall 'devise, endeavour, or intend to deprive or depose' the reigning monarch from the royal style, title, or kingly name of the Imperial Crown of the United Kingdom commits an offense.
The statute specifically targets those who express such intentions 'by publishing any printing or writing.' In theory, this makes writing an article or campaign manifesto arguing for a peaceful transition to a British republic a criminal act punishable by life imprisonment. Despite the law remaining active on the statute books, modern legal consensus holds that the Human Rights Act 1998, which guarantees freedom of expression, effectively neuters the provision.
In 2003, the newspaper The Guardian brought a judicial review challenging the law, but the House of Lords declined to strike it down, declaring that peaceful republican advocacy was no longer prosecuted, making the statute an ancient, un-enforced curiosity.