BLOCKCHAIN AS A GUARANTEE OF THE INTEGRITY OF LEGAL EVIDENCE: LIMITS AND POSSIBILITIES IN THE BRAZILIAN CRIMINAL PROCESS

Abstract

The present chapter focuses on blockchain technology as a mechanism to guarantee the integrity of legal evidence in Brazilian criminal procedure. This is a theoretical and exploratory research, with a qualitative approach and descriptive-analytical character. The objective of the study is to analyze to what extent blockchain can contribute to the preservation of authenticity and immutability of digital evidence, as well as to identify the technical and normative limits for its adoption in forensic context. The methodology adopted comprised a literature review on blockchain, digital evidence and criminal procedure, analysis of the technical properties of the technology, and examination of compatibility with arts. 158-A to 158-F of the Brazilian Code of Criminal Procedure. The main results show that blockchain offers robust solutions to the problem of tampering with digital evidence, especially regarding the documentation of the chain of custody and traceability of traces. However, significant limits were identified, such as the difficulty of reconciling with the adversarial principle and the right to be forgotten. It is concluded that blockchain can be used as a complementary tool to the chain of custody, but it does not replace the need for technical training and specific regulation by the infraconstitutional legislator.