Scientific Evidence and Undeposited Publications: The Criminal Cassation Court No. 15486/2025 Clarifies Admissibility

When an expert or technical consultant bases their conclusions on scientific studies that are not physically produced in court, is their admissibility compromised? The Third Criminal Section of the Cassation Court, with judgment no. 15486 of March 21, 2025 (filed April 18, 2025), answers this question by annulling with referral the decision of the Court of Appeal of Turin. The verdict, destined to impact the practices of all Courts, follows precedents such as Cass. 45935/2019 and 43845/2022, but introduces useful clarifications for the management of scientific evidence in court.

The Procedural Facts and the Controversial Issue

In the case examined, the conclusions of an expert appointed by the parties made extensive reference to research published in foreign specialized journals. However, these articles had not been attached or produced in the trial file. The defendant's defense objected to the inadmissibility of the expert report, invoking the violation of articles 220, 501, and 546, paragraph 1, letter e) of the Code of Criminal Procedure, as well as the principle of adversarial proceedings enshrined in article 111 of the Constitution. The Court of Appeal had rejected the objection, emphasizing the scientific relevance of the cited sources. Hence the appeal to the Cassation Court.

The Principle of Law Affirmed

In matters of scientific evidence, the reference by a technical consultant or expert to publications or studies not produced in the trial file does not affect their admissibility, but pertains to the reliability of the conclusions presented by the expert, which, being based on uncontrollable data, require the judge to evaluate them, taking into account this limitation.

The Court thus distinguishes two levels: on one hand, the procedural admissibility of the expert report (which remains intact); on the other hand, its reliability, which may be diminished if the scientific data referred to remain "uncontrollable" by the parties. Therefore, it is not an absolute defect that invalidates the evidence, but a limit to evaluation that the judicial body is required to explain in its reasoning, pursuant to article 192 of the Code of Criminal Procedure.

Practical Implications for Defense and Prosecution

• Judge's Duty to Provide Reasoning: The trial judge must account for the existence of unverifiable references and explain why, despite this, they consider the expert's conclusions reliable (or not).
• Defense Strategies: The lawyer may not limit themselves to objecting to inadmissibility but must dismantle the credibility of the expert work or request, pursuant to art. 227, paragraph 5, of the Code of Criminal Procedure, an investigative approfondimento.
• Role of the Public Prosecutor: The Public Prosecutor, especially in cases of environmental and health crimes, must assess the opportunity to produce the scientific papers cited, to avoid disputes about the verifiability of the data.
• Best Practices for Consultants: Always attach the cited sources, or deposit them subsequently pursuant to art. 501 of the Code of Criminal Procedure, thus facilitating the adversarial process and the appeal to the Cassation Court.

Finally, the systematic relevance of the principle should not be forgotten: it is part of the dialogue between the need for swiftness in proceedings and the parties' right to critical examination of evidence, in line with Article 6 of the ECHR and the Strasbourg jurisprudence on a fair trial.

Conclusions

Judgment no. 15486/2025 reiterates that, in criminal proceedings, inadmissibility is a category to be applied rigorously and not extended to every evidentiary deficiency. When the studies cited by the expert are missing, the evidence remains formally valid, but its persuasive weight depends on the judge's ability to account for any gray areas. For legal professionals, this means shifting the focus from a mere procedural objection to a substantive confrontation on the scientific method adopted, strengthening the right to defense and the quality of the judgment.