Contemporary democracies are based on three founding principles: i) separation of powers, which balances against excessive centralisation through checks and balances; ii) institutional representation of the people, ensuring an active role for minorities and opposition; iii) citizen participation and transparency in legislative, judicial and administrative processes. Within this framework, this work proposes a multilevel DLT architecture to ensure: a) separation of powers between institutions involved in the legislative process, providing autonomy to various actors (e.g., Chamber, Senate, Government, Ministers); b) active stakeholder participation (e.g., associations, municipalities, regions); c) transparent and public decision-making. A blockchain architecture with three interconnected yet autonomous levels is designed to respect the constitutional separation of powers. This system implements these three principles whilst leveraging blockchain characteristics to ensure traceability, authority, integrity, and selective transparency for publishable information only. The project involves the implementation of three levels of DLT (Private Institutional Blockchain, Inter-Institutional Coordination Blockchain, Public Legislative Blockchain) and the use of the MOVE language to model smart contracts that regulate legislative procedures between institutions. Akoma Ntoso XML OASIS standard will also be used to model legislative documents and track changes introduced by different institutions. Finally, Decentralized Self-Sovereign Identity (SSI) implemented through the IOTA Identity framework will be used for permissioned access in the private blockchain.