Available at http://www.archive.org/details/mirrorofjustices00hornrich
The Mirror of Justices or Speculum Justitiaorum
Author: Horne, Andrew, d. 1328; Corpus Christi College (University of Cambridge). Library. Manuscript. 258; Whittaker, W. J. (William Joseph), 1868-1931; Maitland, Frederic William, 1850-1906

This volume contains a summary of the Law prepared, so Horn tells us, because he

perceived that divers of those who should govern the law by rules of right had regard to their own earthly profit, and to the pleasing of princes and lords and friends, and to the amassing of lordships and goods, and would never assent that the right usages should be put in writing, whereby would be taken from them the power of arresting some by colour of judgment, and of exiling, imprisoning, or disheriting others, without suffering punishment therefor, and when I saw them cloaking their sin by the exceptions of error and ignorance, and having little or no regard to the salvation of the souls of sinners from damnation by lawful judgments, as their office demands, and having hitherto used to judge folk out of their own heads by abuses and precedents of others erring in the law, and not by the right rules of Holy Writ, to the great hindrance of your endeavour, all ye who build without foundation, and take on yourselves to judge before that ye are learned in jurisdiction, which is the very groundwork of your profession, and hold yourselves out as learned in the law of land before ye have mastered the law of persons (like to those who study the Hberal arts before the parts of speech ) : I, the prosecutor of false judges, and falsely imprisoned by their order, in my sojourn [in gaol] searched out the privileges of the king and the old rolls of his treasury, wherewith my friends solaced me, and there discovered the foundation and the generation of the customs of England which are established as law, and the guerdons of good judges and the punishment of others, and as brieflyas I could I set in remembrance what is essential, for which end my companions aided me in the study of the Old Testament and the New, and the canon and the written law…And we discovered that law is nothing else than the rules laid down by our holy predecessors in Holy Writ for the salvation of souls from everlasting damnation, although it be obscured by false judges. (Mirror, pp. 2-3)

Of particular interest is the straightforward Scriptural analogy by which concepts are related; for example, Jurisdiction is defined clearly to be

the power jus dicere. This power God gave to Moses, and this power have those who now hold His place upon earth, such as the pope and the emperor, and beneath them the king has now this power in his realm. (Mirror, p. 123)

Similarly clear justification is given for the proof of a controverted statement by battle,

for this usage is held for law in England by the warrant of our Lord God in the matter of the battle joined between David on behalf of the people of Israel of the one part, and Goliath on the part of the Philistines of the other part, so that proof in cases of felony and in other cases is made by combat. (Mirror, p. 109)

The Mirror is referred to several times in Blackstone’s Commentaries, for example 1 Bl. Comm. 6 concerning the Coronation Oath, which cites the Mirror, Book I Chapter II:

at his crowning they made him swear that he would maintain the Christian faith with all his power, and would guide his people by law without respect of any person, and would be obedient to holy Church, and would submit to justice and would suffer right like any other of his people. And after this the kingdom became heritable. (Mirror, p. 6)

It is questionable how much value this volume possesses contemporarily, for, on the one hand, it does claim to be justified more or less of the Scripture, or, as it’s called during the contemporary coronation, the most valuable thing this world affords, and, an the other hand, it does have its age going for it, which, if I remember an Aristotle anecdote, has one thing going for it: its age.