The use of randomization procedures is motivated by their capacity of shielding processes against all sorts of information biases, extraneous influences, illegitimate interference or spurious manipulations, independently from intention, concealment, or manifestation. In the specific context of legal procedures, random selection is employed by many countries to guarantee that entities like jurors  and judges  , have a pre-defined, although not necessarily uniform, probability of being picked. The goal of adopting this approach is to avoid (the perception of) skewed decisions. Even though it is argued that applying this method directly to the pool of candidates may produce outlier committees that do not represent the collective view of the full set of members, other “representative” procedures still depend on the randomized selection to draw from an ideal pool of committees .
In this scenario, though, randomization comes with two additional requirements: auditability by design and active social engagement. More precisely, auditability by design improves the trust in the system. Hence, it can avoid suspicions commonly raised when statistical deviations are observed in a non-auditable random procedure , even if such biases are not the result of ill-intent. Meanwhile, an active, self-reflective and well-coordinated participation by pertinent members of a community can result in more engagement and inclusiveness, relevant aspects of social practices that also apply to the legal system . Combined, such requirements can help legal systems to achieve an important goal: to ensure that its norms (expressed as laws, procedures and regulations) are well understood, recognized, and valued.
The scientific understanding of randomization procedures is linked to development of mathematical statistics and cryptography. After all, randomness is a critical component of any cryptographic solutions involving secret keys, leading to the need of tools for generating (pseudo)random numbers and for statistically assessing their suitability . Ensuring that the randomness generator can be audited by anyone, on the other hand, is a more challenging issue. Some solutions in the literature rely on the concept of “open hardware”, so anyone with technical enough background can (at a given time) examine and evaluate the internal circuit and components of the hardware responsible for generating randomness . There are also proposals that rely on distributed solutions that are expected to generate randomness as part of its regular operation, such as cryptocurrencies , thus facilitating auditing by non-technicians. One drawback of this approach, however, is that the resulting application’s security and availability may be affected by external events unrelated to the application itself, but typical of the underlying solution (e.g., forks, implementation bugs, or collusion attacks) . Traditionally, auditability of random results has been discussed by protocols for online games involving chance . Nevertheless, the requirements in those applications are commonly different from the drawing in legal procedures, in particular due to the asymmetry of participants (e.g., the casino owner vs. the players) and the focus on strictly uniform probability distributions.
Given this context, we are currently studying auditable random drawing protocols that combine social engagement and support for multiple probability distributions. Blockchains and blockchain-like data structures are of interest in this scenario, either as building blocks for new solutions or as subjects of interest for further investigation (e.g., proposals based on cryptocurrencies, like ). Our goal is to identify and/or propose solutions fulfilling the following requirements: security by design, ensuring the fairness of the random draw as long as at least one participant behaves honestly; auditability by any interested party using only public information accessible even by people with no technical background,; and statistical robustness, supporting drawings where candidates may have distinct probability distributions.
This research project is supported by the University Blockchain Research Initiative (UBRI).
Contact information at USP: Prof. Dr. Marcos A. Simplicio Jr <mjunior(at)larc.usp.br>, Prof. Dr. Julio M. Stern <jstern(at)ime.usp.br>, and Prof. Dr. Roberto A. C. Pfeiffer <roberto.pfeiffer(at)usp.br>
- Marcos V. M. Silva, Marcos A. Simplicio Jr, Roberto A. C. Pfeiffer, Julio M. Stern. (2020) “A Fair, Traceable, Auditable and Participatory Randomization Tool for Legal Systems”. ArXiv preprint. Available: https://arxiv.org/abs/2006.02956
- Julio M. Stern, Marcos A. Simplicio Jr, Marcos V. M. Silva, Roberto A. C. Pfeiffer. (2020) “Randomization and Fair Judgment in Law and Science”. A True Polymath: A Tribute to Francisco Antonio Doria. Rickmansworth, UK: College Publications. ISBN: 978-1-84890-351-7 (Jose Acacio de Barros and Decio Krause, eds.). Available: https://arxiv.org/abs/2008.06709
- Tomas Novaes (2021). Professores da USP desenvolvem sistema de sorteio para o Judiciário com a tecnologia blockchain . Available (PT-BR): http://aun.webhostusp.sti.usp.br/index.php/2021/07/06/professores-da-usp-desenvolvem-sistema-de-sorteio-para-o-judiciario-com-a-tecnologia-blockchain/
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