In our day and age the medieval institution of sanctuary is hard to understand. Sanctuary allowed criminals to escape punishment simply by taking refuge in a church. To some historians it appears to have been a craven capitulation by temporal rulers to an assertion of power by the medieval Church. But that hardly explains its ubiquity and longevity. Karl Shoemaker's efforts provide guidance. It has also been an occasion for reflection by this reviewer. Perhaps someday the routine discharge of debts in bankruptcy law will seem equally incomprehensible to observers. The system allows debtors to escape legitimate claims. Yet most of us accept it with equanimity. If this system ever changes, future observers will need a book like Shoemaker's to explain why statutory cancellation of debts once seemed to make sense.

The book covers three periods. The first is late antiquity. For it, the relevant sources are writings of the church Fathers, Roman law (in particular the Theodosian Code) and the laws of the Germanic kingdoms. The second is English law from the Anglo-Saxons to 1500. The relevant sources are the laws and chronicles of the earlier period and the plea rolls of the royal courts for the later. The third is the canon law as developed from ancient texts during the twelfth century to the sixteenth. The relevant sources are the texts of the Corpus iuris canonici and the learned commentaries written by the jurists of the ius commune. The book is thus less than the ‘comprehensive monograph’ suggested by the title. Little is said, for example, about the status and enforcement of sanctuary law on the continent during the later medieval period. One wonders whether medieval statutes and books of consilia and decisiones might not have yielded some useful evidence. With that limitation, the author provides an excellent guide to each of the subjects that the book takes up.

The first section is probably the most surprising and original of the three. The puzzle is to understand why ‘nearly every medieval legislative source – ecclesiastical or secular – announces some form of protection for criminals who took sanctuary’ (p. xii). Why should the emperors and their successors – men not often cowed by clerical pretensions – have endorsed this obvious evasion of their laws? And why should the clergy themselves have welcomed criminals as guests within their sacred precincts? The answer given to the first question is that historians have misunderstood what sanctuary meant to medieval kings. It was actually ‘a vehicle’ that the kings used to ‘express social and political power’ (p. 49). Just as the issuance of pardons in criminal law today might be regarded as a sign of a governor's untrammeled authority, so it was with the establishment of sanctuary in the early Middle Ages. Far from being a concession to the Church by cowardly monarchs, grants of sanctuary actually enhanced their status as rulers. The answer to the second question is that the clergy regarded sanctuary as an opportunity to carry out their duty. The Gospels required them to intercede for the world's unfortunate and also to reconcile penitent sinners with God. Sanctuary offered a chance to do both, and the clergy seized the opportunity. The punishment of criminals thus took second place to ‘the twin foundations of episcopal intercession and penitential discipline’ (p. 27). The apparent absence of public prosecution of crime in so much early medieval law also fits neatly within this clerical perspective.

The early English evidence is of a piece with the continental. Recognition of ecclesiastical sanctuary was not ‘a concession of weakness but an emblem of strength’ to the Anglo-Saxon kings. Here, the author embraces and advances the views of the late Patrick Wormald. The Norman kings built upon the Anglo-Saxon achievement in sanctuary law as in so much else. What then happened under the Angevins is that the law ‘regularized the processes that governed sanctuary’ (p. 113), in the process establishing the system of abjuration of the realm that is familiar to historians of the common law. That it was not identical to the institution endorsed by the canon law is an indication of the precocious independence of the common law. The book explores the system's mechanics, including some of the apparently difficult problems it encountered – as for instance the ‘chartered sanctuaries’ that stood somewhat outside the system, and also the problem of ‘timid men’ (and women) who claimed falsely to have committed a crime in order to escape their enemies. The system of royal pardons is also well described.

The third section deals with the demise of medieval sanctuary, ascribing it largely to ‘an intellectual transformation within canon law’ (p. 152). This turns conventional thinking on its head. The Church was not an embattled defender of this privilege. In fact, large and growing classes of offenders were excluded from sanctuary by the law of the Church itself. ‘Jews, heretics, ravishers of maidens, traitors, blasphemers, homicides, exiles’ (p. 172) along with many, many others could be removed from churches where they had taken refuge. This development occurred because of the growing conviction among theologians and jurists that proper punishment of criminals was necessary to protect the social fabric. When Henry viii and Francis i attacked sanctuary in England and France, therefore, they were following principles ‘laid out within the canon law itself’ (p. 154). Not least among the merits of this monograph is the advance in understanding that this perspective brings with it.