The Hidden Value of Patterns – Using Design Patterns to Whitebox Technology Development in Legal Assessments

Higher legal standards with regards to data protection of individuals such as the European General Data Protection Regulation (GDPR) increase the pressure on developing lawful technologies. The development requires feedback from stakeholders such as legal experts that lack technical knowledge but are required to understand IT artifacts. As a solution, patterns can support interdisciplinary system development. We demonstrate how interdisciplinary patterns can support legal experts in arguing about technologies in court by introducing a law simulation study which is a well-known evaluation method in law. Our results show that patterns support legal experts in their argumentation about technologies in court. We provide theoretical contributions concerning cognitive fit theory about how patterns act as a bridge between the internal and external representation of problems and improve problem-solving performance related to the legal assessment of technology. In addition, we provide practical guidance for codifying and communicating design knowledge through patterns.