The Mirror of Justices

The Mirror of Justices, also known in Anglo-Norman as Le mireur a justices and in Latin as Speculum Justitiariorum, is a medieval Anglo-Norman legal epitome that sets out common law procedure and attacks what the author calls "abuses" in legal practice and legislation. It survives in a single early fourteenth-century manuscript in the Parker Library (Corpus Christi College, Cambridge, MS 258). Modern scholarship usually dates it to between 1285 and 1290, after Statute of Westminster II and the Statute of Merchants but before the statute Quia Emptores.

The work is traditionally attributed to Andrew Horn, a London fishmonger and lawyer who later served as Chamberlain of the City of London, but recent scholarship has found this attribution to be unsound. The author presents himself as a "prosecutor of false judges" who was "falsely imprisoned", framing the treatise as a short summary of the law while pressing for reform. The text is organised into five chapters on offences, plaintiffs' procedure, defendants' procedural answers, judgments and jurisdiction, and complaints about the law. The legal material sits alongside invented content, including a fictional "original constitution" attributed to Alfred the Great.

The text circulated among Tudor lawyers as a pre-Conquest authority, and was cited in seventeenth century parliamentary debates. It entered print in French in 1642 and in an English translation in 1646, and was repeatedly reprinted. The Selden Society edition of 1895, with an introduction by Frederic Maitland, discredited the Mirror as reliable evidence for early English law.