Blockchain has the capacity to transform the industries disruptively as it presents new features like smart contracts, tokenization of content, eliminating counterfeit products, supply chain improvement, digital twins, and end-to-end security. This letter presents a Diamond Accountability Model (DAM) where a public or private authority is included in the blockchain transactions providing non-repudiation of digital transactions, holistic security and effective governance. The proposed technique aims to present a decentralized solution for multi-agent applications where many partnering organizations have to collaborate without suffering from the security, accountability, maintenance, scalability, and integrity problems over distributed cyber-physical systems (CPS). The proposed scheme positions authorities also in the chain that enables additional accountability and trust. The scheme proposes a verification mechanism where the authorized organizations are also included in the verification of transactions over the blockchain. In order to elucidate, a conceptual use case is presented where at least two partnering organizations collaborate with each other within a decentralized but also authorized blockchain-enabled scheme.