The legal treatises of the Kingdom of Jerusalem were written in the thirteenth century, when most of the kingdom had been re-conquered by the Muslims. There are no treatises from the twelfth century, when the kingdom was at its height. The thirteenth-century jurists claimed that the kingdom had always had written laws, but they may have been making this up for political purposes. The treatises also discuss issues important to the noble class of which the jurists were a part: property rights and the feudal services owed to the king, as well as the proper way to plead their cases in court. But what do they say about criminal law, and laws for the lower classes? How were crimes tried and punished in the twelfth century, and did this differ from the laws recorded in the thirteenth century? Chapter one deals with the different treatises, and their claim that there was a set of laws called “Letres dou Sepulcre” in the twelfth century. The most important of the treatises for criminal law, the assizes of the burgess court, is examined in detail. Chapter two looks at the small number of laws that survive from the twelfth century, in charters, the canons of the Council of Nablus, and the chronicle of William of Tyre. Chapter three is a study of other descriptions of crusader law in the twelfth century, including those by Christian and Muslim pilgrims, and especially the observations of Usama ibn Munqidh. These accounts are tied together by the common theme of theft and the ways that thieves could be punished. Chapter four deals with cases mentioned by thirteenth-century sources, including theft, assault, and prostitution, but especially cases that led to trials by battle. The usefulness of such trials for dating some of the laws is also examined. The conclusion demonstrates that certain parts of the assizes relating to criminal law must have already existed in the twelfth century, and offers some tentative ideas about the specific origin of the laws. Avenues for future research are also introduced.

The legal treatises of the Kingdom of Jerusalem were written in the thirteenth century, when most of the kingdom had been re-conquered by the Muslims. There are no treatises from the twelfth century, when the kingdom was at its height. The thirteenth-century jurists claimed that the kingdom had always had written laws, but they may have been making this up for political purposes. The treatises also discuss issues important to the noble class of which the jurists were a part: property rights and the feudal services owed to the king, as well as the proper way to plead their cases in court. But what do they say about criminal law, and laws for the lower classes? How were crimes tried and punished in the twelfth century, and did this differ from the laws recorded in the thirteenth century? Chapter one deals with the different treatises, and their claim that there was a set of laws called “Letres dou Sepulcre” in the twelfth century. The most important of the treatises for criminal law, the assizes of the burgess court, is examined in detail. Chapter two looks at the small number of laws that survive from the twelfth century, in charters, the canons of the Council of Nablus, and the chronicle of William of Tyre. Chapter three is a study of other descriptions of crusader law in the twelfth century, including those by Christian and Muslim pilgrims, and especially the observations of Usama ibn Munqidh. These accounts are tied together by the common theme of theft and the ways that thieves could be punished. Chapter four deals with cases mentioned by thirteenth-century sources, including theft, assault, and prostitution, but especially cases that led to trials by battle. The usefulness of such trials for dating some of the laws is also examined. The conclusion demonstrates that certain parts of the assizes relating to criminal law must have already existed in the twelfth century, and offers some tentative ideas about the specific origin of the laws. Avenues for future research are also introduced.