Digital Evidence in Romanian Criminal Proceedings: Computational Challenges, Procedural Safeguards and Artificial Intelligence-Based Tools

Digital evidence is now present in almost every criminal case, yet it is volatile, easily altered and difficult to verify for a judge without technical training. The Romanian Code of Criminal Procedure requires computer searches to preserve the integrity of data, but the cryptographic safeguards it mentions, such as electronic signatures, remain optional. This article aims to translate the procedural guarantees of domestic and European law (Regulation (EU) 2023/1543, Directive (EU) 2016/680, and the case law of the European Court of Human Rights and of the Court of Justice of the European Union) into verifiable technical requirements. The methodology combines normative and case-law analysis with a review of digital forensics standards. On this basis, we propose a chain-of-custody model built on an append-only ledger chained through hash functions, electronic signatures, timestamps issued by a third party and a Merkle tree for data minimisation. The model was implemented as a Python prototype and evaluated on synthetic data. Internal verification of the ledger detected every alteration in 11 of 13 tampering scenarios, each tested in 1,000 trials. Truncation of the ledger and its complete rewriting by colluding operators were detected only when the final ledger value was anchored with an independent third party, in which case the detection rate reached 100%. The mechanism added about 0.75–0.80 s of computation per GiB of data, verification took about 0.19 ms per record, and Merkle proofs stayed below 640 bytes for one million files. We conclude that the integrity of digital evidence can be demonstrated rather than merely presumed, provided that data signing and external anchoring become mandatory. We also show that AI-based triage tools, which largely fall outside the high-risk category of the AI Act, create specific risks for the defence and should be recorded in the same chain of custody.

Digital evidence, chain of custody, digital forensics, Merkle tree, artificial intelligence

1. Akhlaghi M. (2025). Laboratoire de cyberjustice. Deepfakes in courtrooms: How judges are adapting to a new reality. Université de Montréal. https://cyberjustice.openum.ca/s/24524 [Google Scholar] [Crossref]

2. Antoci, A., & Cozma, T.-M. (2025). Autenticitatea și integritatea probelor electronice în procesul penal: provocări teoretico-practice [Authenticity and integrity of electronic evidence in criminal proceedings: Theoretical and practical challenges]. Revista Națională de Drept, 2(254), 38–46. https://doi.org/10.52388/1811-0770.2025.2(254).04 [Google Scholar] [Crossref]

3. Apostol, A. (2023). Case study on the effects of Constitutional Court Decision No. 51/2016 on pending proceedings. Analele Universității „Dunărea de Jos” din Galați, Fascicula XXVI: Științe juridice, 6(2), 35–47. https://www.ceeol.com/1278712 [Google Scholar] [Crossref]

4. Ayers, R., Brothers, S., & Jansen, W. (2014). Guidelines on mobile device forensics (NIST Special Publication 800-101 Rev. 1). National Institute of Standards and Technology. https://doi.org/10.6028/NIST.SP.800-101r1 [Google Scholar] [Crossref]

5. Barbu, D., & Ghebaru, P. D. (2026). Percheziția informatică: când telefonul tău devine martor împotriva ta [The computer search: When your phone becomes a witness against you]. Universul Juridic. https://www.ujmag.ro/drept/perchezitia-informatica [Google Scholar] [Crossref]

6. Brezinski, D., & Killalea, T. (2002). Guidelines for evidence collection and archiving (RFC 3227). Internet Engineering Task Force. https://doi.org/10.17487/RFC3227 [Google Scholar] [Crossref]

7. Buneci B. (2019). Percheziţia informatică – procedeu probatoriu pentru descoperirea, identificarea şi strângerea probelor stocate într-un sistem informatic [The computer search: An evidentiary procedure for discovering, identifying and gathering evidence stored in a computer system]. Instrumentul Bibliometric Național. Științe juridice. https://ibn.idsi.md/ [Google Scholar] [Crossref]

8. Carrier, B. (2005). File system forensic analysis. Addison-Wesley Professional. https://scholar.google.com/ [Google Scholar] [Crossref]

9. Casey, E. (2011). Digital evidence and computer crime: Forensic science, computers and the Internet (3rd ed.). Academic Press. https://scholar.google.com/ [Google Scholar] [Crossref]

10. CCBE. (2025). CCBE response to the targeted stakeholder consultation on the implementation of the AI Act's rules for high-risk AI systems. Council of Bars and Law Societies of Europe. https://www.ccbe.eu/ [Google Scholar] [Crossref]

11. CEPEJ. (2018). European ethical charter on the use of artificial intelligence in judicial systems and their environment. Council of Europe. https://rm.coe.int/ethical-charter [Google Scholar] [Crossref]

12. Ciorea, P. (2017). Considerații asupra percheziției informatice [Considerations on the computer search]. Penalmente Relevant, (1). https://www.ceeol.com/555336 [Google Scholar] [Crossref]

13. Constitutional Court of Romania. (2009). Decision no. 1258 of 8 October 2009 on the plea of unconstitutionality of the provisions of Law no. 298/2008. https://legislatie.just.ro [Google Scholar] [Crossref]

14. Constitutional Court of Romania. (2016). Decision no. 51/2016 on the plea of unconstitutionality of the provisions of Article 142(1) of the Code of Criminal Procedure. https://www.ccr.ro/ [Google Scholar] [Crossref]

15. Constitutional Court of Romania. (2017). Decision no. 244 of 6 April 2017 on the plea of unconstitutionality of the provisions of Article 145 of the Code of Criminal Procedure. MO, Part I, no. 529 of 6 July 2017. https://www.ccr.ro [Google Scholar] [Crossref]

16. Council of Europe. (2024). Framework Convention on Artificial Intelligence and Human Rights, Democracy and the Rule of Law (CETS No. 225). https://www.coe.int/ [Google Scholar] [Crossref]

17. Council of Europe. (2026, May 15). European Union ratifies the Council of Europe Framework Convention on Artificial Intelligence. https://www.coe.int/en/web/artificial-intelligence [Google Scholar] [Crossref]

18. Court of Justice of the European Union. (2024a). Judgment of 30 April 2024, M.N. (EncroChat), C-670/22. ECLI:EU:C:2024:372. [Google Scholar] [Crossref]

19. Court of Justice of the European Union. (2024b). Judgment of 4 October 2024, C.G. v Bezirkshauptmannschaft Landeck, C-548/21, ECLI:EU:C:2024:830. [Google Scholar] [Crossref]

20. Crișan, E. G. (2017). Rolul percheziției informatice în probarea infracțiunilor contra drepturilor de proprietate intelectuală [The role of the computer search in proving offences against intellectual property rights]. Acta Universitatis Sapientiae, Legal Studies, 6(2), 249–258. https://acta.sapientia.ro/ [Google Scholar] [Crossref]

21. Crosby, S. A., & Wallach, D. S. (2009). Efficient data structures for tamper-evident logging. In Proceedings of the 18th USENIX Security Symposium. USENIX Association. https://www.usenix.org/ [Google Scholar] [Crossref]

22. Directive (EU) 2016/680 of the European Parliament and of the Council of 27 April 2016 on the protection of natural persons with regard to the processing of personal data by competent authorities for the purposes of the prevention, investigation, detection or prosecution of criminal offences or the execution of criminal penalties, and on the free movement of such data, and repealing Council Framework Decision 2008/977/JHA. Official Journal of the European Union, L 119, 4.5.2016, 89–131. https://eur-lex.europa.eu/eli/dir/2016/680/oj [Google Scholar] [Crossref]

23. Directive (eu) 2023/1544 of the european parliament and of the council laying down harmonised rules on the designation of designated establishments and the appointment of legal representatives for the purpose of gathering electronic evidence in criminal proceedings. Oficial Journal of European Union. Eur-Lex, L 191. CELEX 3A32023L1544 [Google Scholar] [Crossref]

24. Directive 2014/41/eu of the european parliament and of the council regarding the European Investigation Order in criminal matters. Oficial Journal of European Union. Eur-Lex, L 130. CELEX32014L0041 [Google Scholar] [Crossref]

25. Dushi, D., & Marcu, B.-I. (2026). Red lines under the EU AI Act: Unpacking the prohibition of individual risk assessment for the prediction of criminal offences. Future of Privacy Forum. https://fpf.org/ [Google Scholar] [Crossref]

26. ENFSI. (2026). Best practice manual for the forensic examination of documents (ENFSI-BPM-FIT-01). European Network of Forensic Science Institutes. https://enfsi.eu/ [Google Scholar] [Crossref]

27. European Commission. (n.d.). AI Act Service Desk: Law enforcement. Use cases classified as high-risk (Annex III, point 6). https://ai-act-service-desk.ec.europa.eu/de/node/466 [Google Scholar] [Crossref]

28. European Commission. (2024). AI Act Explorer. Regulation (EU) 2024/1689 of the European Parliament and of the Council of 13 June 2024 laying down harmonised rules on artificial intelligence (Artificial Intelligence Act). Official Journal of the European Union, L 2024/1689, 12.7.2024. CELEX 202401689 [Google Scholar] [Crossref]

29. European Court of Human Rights. (2023). Yüksel Yalçınkaya v. Türkiye [GC], application no. 15669/20, judgment of 26 September 2023. https://hudoc.echr.coe.int/ [Google Scholar] [Crossref]

30. European Union (2024). Regulation (EU) 2024/1183 of the European Parliament and of the Council of 11 April 2024 amending Regulation (EU) No 910/2014 as regards establishing the European Digital Identity Framework. Official Journal of the European Union, L 257. CELEX 32024R1183 [Google Scholar] [Crossref]

31. European Union (2026). Digital omnibus regulation on AI. Regulation (EU) 2026/1744 as regards the simplification of the implementation of harmonised rules on artificial intelligence. Official Journal of the European Union. Eur-Lex. Access to European Union Law. CELEX 32026R1744 [Google Scholar] [Crossref]

32. Golaszewski, E., Krawetz, N., Sherman, A. T., Zieglar, E., Matukumalli, S. K., Yus, R., Kegley, C. L., Barthel, M., Bowman, W., Barot, B., & Kullman, K. (2026). Verifying provenance of digital media: Why the C2PA specifications fall short. https://doi.org/10.48550/arXiv.2604.24890 [Google Scholar] [Crossref]

33. Grădinaru, S. (2024). Controversies regarding the legality of interceptions carried out through the National Center for Interception of Communications within the Romanian Information Service. Annals of 'Dunarea de Jos' University of Galati: Legal Sciences (ALS), Fascicle XXVI, 2024, v. 7, n. 1, p. 55. ISSN 2601-9779. https://www.gup.ugal.ro/ugaljournals/ [Google Scholar] [Crossref]

34. High Court of Cassation and Justice, Criminal Division. (2014). Interlocutory ruling no. 3147 of 12 December 2014. https://www.scj.ro [Google Scholar] [Crossref]

35. High Court of Cassation and Justice, Criminal Division. (2024). Decision no. 642 of 25 September 2024. https://www.scj.ro [Google Scholar] [Crossref]

36. High Court of Cassation and Justice, Panel for the Resolution of Points of Law in Criminal Matters. (2018). Decision no. 2 of 8 February 2018. https://www.scj.ro [Google Scholar] [Crossref]

37. High Court of Cassation and Justice, Panel for the Resolution of Points of Law in Criminal Matters. (2023). Decision no. 56 of 18 September 2023 (case no. 1.235/1/2023). Monitorul Oficial al României, Part I, no. 910 of 10 October 2023. https://www.scj.ro [Google Scholar] [Crossref]

38. ISO/IEC Standard, International. (2014). Information technology — Security techniques — Guidelines for identification, collection, acquisition and preservation of digital evidence. International Organization for Standardization. igital Evidence and Electronic Signature Law Review. 10.14296/deeslr.v10i0.2015 [Google Scholar] [Crossref]

39. Kent, K., Chevalier, S., Grance, T., & Dang, H. (2006). Guide to integrating forensic techniques into incident response (NIST Special Publication 800-86). National Institute of Standards and Technology. https://doi.org/10.6028/NIST.SP.800-86 [Google Scholar] [Crossref]

40. Law no. 135/2010 on the Code of Criminal Procedure, published in Monitorul Oficial al României, Part I, no. 486 of 15 July 2010, as subsequently amended and supplemented. https://legislatie.just.ro [Google Scholar] [Crossref]

41. Law no. 64/2004 ratifying the Council of Europe Convention on Cybercrime, adopted in Budapest on 23 November 2001, published in Monitorul Oficial al României, Part I, no. 343 of 20 April 2004. https://legislatie.just.ro/51288 [Google Scholar] [Crossref]

42. Legislative Observatory. European Parliament (2023). Electronic evidence regulation: European production and preservation orders for electronic evidence in criminal matters. Official Journal of the European Union, L 191, 28.7.2023, 118–180. https://oeil.europarl.europa.eu/ [Google Scholar] [Crossref]

43. Lone, A. H., & Mir, R. N. (2019). Forensic-chain: Blockchain based digital forensics chain of custody with PoC in Hyperledger Composer. Digital Investigation Journal, V 28, Pages 44–55. https://doi.org/10.1016/j.diin.2019.01.002 [Google Scholar] [Crossref]

44. Merkevičius, R. (2024). Judgment of the Court of Justice of the European Union of 30 April 2024 in the "EncroChat case" (case No. C-670/22): Does this judgment really legitimise forum shopping in criminal proceedings, and how will it impact Lithuanian criminal proceedings? Teisė, 132, 20–36. https://doi.org/10.15388/Teise.2024.132.2 [Google Scholar] [Crossref]

45. Merkle, R. C. (1988). A digital signature based on a conventional encryption function. In C. Pomerance (Ed.), Advances in Cryptology - CRYPTO '87 (Lecture Notes in Computer Science, Vol. 293, pp. 369–378). Springer. https://doi.org/10.1007/3-540-48184-2_32 [Google Scholar] [Crossref]

46. Moise, A. C. (2024). Some Applications of the Artificial Intelligence in the Field of Forensic Investigation. Analele Stiintifice Ale Universitatii Alexandru Ioan Cuza Din Iasi Stiinte Juridice, 70, 39. https://access.heinonline.com/ [Google Scholar] [Crossref]

47. Murariu, A.-S. (2023). Contestarea, în procedura camerei preliminare, a încheierii judecătorului de drepturi și libertăți prin care s-a admis măsura de supraveghere tehnică [Challenging, in the preliminary chamber procedure, the ruling of the judge of rights and liberties authorising technical surveillance]. Revista Universul Juridic, (9), 21–31. https://www.ceeol.com/1235553 [Google Scholar] [Crossref]

48. National Institute of Standards and Technology. (2015). Secure hash standard (SHS). Federal Information Processing Standards Publication (180-4). https://doi.org/10.6028/NIST.FIPS.180-4 [Google Scholar] [Crossref]

49. Neagu, I., & Damaschin, M. (2020). Tratat de procedură penală. Partea generală [Treatise on criminal procedure: General part] (3rd ed.). Universul Juridic. https://scholar.google.com/ [Google Scholar] [Crossref]

50. Pintea, F.-A. (2026). Prototip de lanț de custodie verificabil criptografic pentru probe digitale [Prototype of a cryptographically verifiable chain of custody for digital evidence] (Version 1.0.0) [Software]. Zenodo. https://doi.org/10.5281/zenodo.23519444 [Google Scholar] [Crossref]

51. Roibu M., Costăchescu Ș. and Petrușan N. (2026). Electronic evidence in criminal investigations. New obligations for communications service providers. Lawyers Week Journal. https://lawyersweek.net/ [Google Scholar] [Crossref]

52. Romanian Senate, Foreign Policy Committee. (2026). Sinteza lucrărilor Comisiei pentru politică externă [Summary of the proceedings of the Foreign Policy Committee] (L272/2026). https://www.senat.ro/ [Google Scholar] [Crossref]

53. Sandhu, R., Schneier, B., & Kelsey, J. (1999). Secure audit logs to support computer forensics. ACM Transactions on Information and System Security (TISSEC), V 2, no. 2, 1999, pp. 159-176. https://doi.org/10.1145/317087.317089 [Google Scholar] [Crossref]

54. Serban, A. & Marcu, B.-I. (2026). The AI Act implementation timeline: What changes under the AI Omnibus?. Future of Privacy Forum, https://fpf.org/ai [Google Scholar] [Crossref]

55. Stevens, M., Bursztein, E., Karpman, P., Albertini, A., & Markov, Y. (2017). The first collision for full SHA-1 (Cryptology ePrint Archive, Paper 2017/190; revised version of the paper presented at CRYPTO 2017). https://eprint.iacr.org/2017/190 [Google Scholar] [Crossref]

56. Timișoara Court of Appeal. (2019). Interlocutory ruling no. 121 of 14 October 2019, case no. 654/59/2019. https://portal.just.ro [Google Scholar] [Crossref]

57. Udroiu, M. (Coord.). (2020). Codul de procedură penală. Comentariu pe articole [The Code of Criminal Procedure: Article-by-article commentary] (3rd ed.). C.H. Beck. https://scholar.google.com/Codul de procedură penala [Google Scholar] [Crossref]

58. Volonciu, N., et al. (2007). Codul de procedură penală. Comentariu pe articole [The Code of Criminal Procedure: Article-by-article commentary] (4th ed.). Hamangiu. ISBN 978-606-27-2523-5. https://scholar.google.com/ [Google Scholar] [Crossref]

59. Wang, X., & Yu, H. (2005). How to break MD5 and other hash functions. In Annual international conference on the theory and applications of cryptographic techniques. Berlin, Heidelberg: Springer Berlin Heidelberg. Vol. 3494, pp. 19–35. https://doi.org/10.1007/11426639_2 [Google Scholar] [Crossref]

60. Wasim A. & Fahim A. (2024). Human Rights and Technology: Exploring How Technological Advancements Impact Human Rights, Particularly in Surveillance and Data Collection. International-Journal-of-Arts-and-Humanities-Studies. 4(4):19-27. https://doi.org/10.32996/Ijahs.2024.4.4.4 [Google Scholar] [Crossref]

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