Elizabeth Makowski has made her special subject the history of canon law and religious women in the later middle ages. Her insights often have served as a corrective to more naive earlier readings, included those by earlier feminists. Indeed, as she made clear in her first book, Canon Law and Cloistered Women (1997), the oft-cited Periculoso as issued by Boniface VIII (1298) was not immediately enforced or enforceable, and not before a wide range of illustrious canon lawyers had weighed in. Moreover, the text itself was considerably different from the Periculoso of the Council of Trent (1563).  In a second volume, "A Pernicious Sort of Woman;" Quasi-Religious Women and Canon Lawyers in the Later Middle Ages (2005), Makowski took up the difficulties of new types of religious women, particularly beguines and secular canonesses who took only temporary vows. A third volume, English Nuns and the Law (2011) considers the wealthiest communities of cloistered nuns in England, houses like the Bridgettine community of Syon, who protected their property and their enclosure by turning to lawyers to argue their cases in court. Obviously only relatively wealthy communities of religious women could afford such legal expertise; other communities of nuns were often the losers in such legal disputes.
In her latest book, Apostate Nuns in the Later Middle Ages (2019), Makowski turns back to nuns who took permanent vows. Sometimes, but only occasionally, they ran away or contested their vows. Some secured confirmation of the invalidity of those alleged vows. This was often by papal appeal, as in the case of Margaret Prestwich (54), who had been compelled to enter a Benedictine house at age eight; she protested that she did not want to become a nun but was forcibly blessed as one. Eventually, she escaped, married, and received episcopal invalidation of her vows, making her marriage legitimate.
Makowski reminds us of notorious cases, like that of Lucrezia di Francesco Buti (b. 1433) (98) whose lover was the famous Carmelite painter Fra Filippo Lippi (1406-1469). The events were described in Georgio Vasari's 1550 Lives of the Artists, though there are many questionable aspects in Vasari's account that Makowski joins other historians in pointing out. Her steps are somewhat less sure in treating another narrative source, the account by the reformer Johannes Busch's Chronicon Windeshemense, an accountwhich has seen much less scrutiny by historians. Makowski includes the outlines Busch's accounts of returning apostate nuns to enclosed communities, describing their self-congratulatory tone. She describes him as he tells his audience how everyone commented on his extraordinary purity in being able to travel alone with an apostate nun. But Makowski only begins the task of questioning Busch's veracity and motives with regard to these apostates from the nobility who were returned to monastic communities. We now know from the work of the late June Mecham that by introducing stricter monastic practices and reform abbesses, Busch gained a much-vaunted success in introducing Observant Reforms, but probably created the occasion for the apostasy of other religious women. 
More work could be done on the issues of reform and apostasy, but Makowski has made a wonderful start. She shows howmuch variety there was among those nuns accused of apostasy. Many had entered religion by "force or fear," or had not really professed at all. Some ran off willingly with lovers; some were carried off by men seeking to make claims to their inherited property. Some made appeals, even to the pope, that they were being subjected to much harsher rules than those which they had professed. All, like the apostate monks with whom they are compared, were subject to excommunication and punishment, but it could be agreed that those monks become secular priests, holding prebends or serving parishes. But nuns, unlike those monks who apostatized, had no other religious alternatives. Such women, in apostasy, were not equal or equivalent to religious men. Moreover, such women have been viewed throughout history with an unfortunately prurient gaze. Here Makowski provides instead a sympathetic view, respecting them for the difficulty of living in the strictures of enclosure, poverty, and obedience. This is a very useful viewpoint, meaning that in her fourth volume, like the previous three, Makowski provides an important guide to a clearer understanding of medieval religious women. Its conclusions badly need to be incorporated into standard histories of monasticism. I sincerely hope they will be.
1. The strictures of Trent's version cannot be read back as applying to fourteenth- and fifteenth-century nuns.
2. As is clear in the case of Wienhausen, for instance, Busch confiscated monastic treasure, and dragged away important community leaders and anyone else who did not agree with the new practices. See June Mecham's Sacred Communities: Shared Devotions: Gender, Material Culture, and Monasticism in Late Medieval Germany, edited after her sudden death by Constance H. Berman, Alison Beach, and Lisa Bitel (Turnhout: Brepols, 2014).