A Unifying Model of Legal Smart Contracts

Legal smart contracts have been a subject of research for decades, especially since the fusion of deontic logic with traditional programming poses significant challenges. The issue of how to develop and verify legal smart contracts is growing in importance, not least due to the rapid adoption of blockchain-based smart contracts. In this paper, we want to pave the way towards a model-driven approach at legal smart contract development. To this end, we combine insights from literature in law and legal informatics with capabilities of existing modeling approaches and give a unifying model that encapsulates essential components of legal smart contracts. The unifying model may be used as a reference for language designers aiming at a holistic representation of legal smart contracts in a model-driven architecture. It may further serve as a basis for comparing existing modeling frameworks, which we demonstrate by applying it to a set of eight distinct languages.