This book investigates the complex legal and ethical legitimacy of retrospective rule-making within the framework of the rule of law. Charles Sampford, a scholar of legal theory and institutional design, utilizes a combination of historical analysis and normative jurisprudence to evaluate how governments and courts employ retroactive measures. He argues that while a primary objection to retrospective law exists, it is not an absolute prohibition, suggesting that certain contexts necessitate such measures to maintain a well-ordered society.

Legal scholars and practitioners frequently cite this work as a nuanced contribution to the debate on legislative retroactivity. Experts highlight the text for its ability to challenge binary views on the rule of law by demonstrating the functional necessity of retrospective measures in specific legal scenarios.