Admissibility of Wiretaps

Audio vs. Transcripts in Criminal Proceedings

doi: 10.32577/mr.2026.3.15

Abstract

Introduction: The use of wiretap recordings obtained through covert intelligence gathering and the use of covert devices as evidence in criminal proceedings has long been a subject of scrutiny, particularly with regard to their probative value and objectivity. At the same time, it is unclear whether the contents of transcripts prepared during the analysis of audio recordings can be used without playing the original recordings, or to what extent the reading of such transcripts in court proceedings complies with the requirements of due process.

Objectives: The aim of this study is to determine under what conditions audio recordings obtained through wiretapping conducted during covert information gathering and the use of covert devices, as well as their transcripts, may be considered objective evidence in criminal proceedings.

Methodology: The research is based on a dogmatic legal analysis grounded in the interpretation of the evidentiary system of criminal proceedings and the legal framework governing the use of covert intelligence gathering and covert devices. In this study, the author compares the specific characteristics of audio recordings and transcripts as interpreted in the context of evidence based on objective evidence, taking into account the principle of the directness of judicial evidence and the requirements for the enforcement of rule-of-law guarantees. The analysis places particular emphasis on the issue of the objectivity of evidence, as well as the examination of potential sources of distortion arising during the evidentiary process.

Results: According to the results of the study, the hearing of original audio recordings obtained through covert information gathering and the use of covert devices during a trial ensures the highest degree of objectivity in evidence, as these directly reflect the full context of the communication, including emphasis, intonation and other nonverbal elements. In contrast, transcripts are necessarily the result of an interpretive process, during which the selection, structuring, and linguistic recording of content are influenced by subjective factors. Transcripts may therefore distort the original meaning and are unable to fully convey the informational content of audio recordings. The study also highlights that the use of transcripts as exclusive or primary evidence may violate the principles of immediacy and due process.

Conclusion: The primary finding of the research is that, in criminal proceedings, only the original audio recordings obtained through covert information gathering and the use of covert devices can be considered fully valid as objective evidence. Another important finding is that transcripts can only be used in a supplementary capacity, in conjunction with the audio recordings, and cannot be endowed with independent probative value. A relevant direction for future research is to examine how technological advancements – particularly artificial intelligence-based audio processing – may influence the assessment of the evidentiary value of audio recordings and transcripts.

Keywords:

secret information gathering wiretapping audio recording transcription criminal proceedings objective evidence evidentiary procedure metadata

How to Cite

Bálint, T. (2026). Admissibility of Wiretaps: Audio vs. Transcripts in Criminal Proceedings. Hungarian Law Enforcement, 26(3), 231–248. https://doi.org/10.32577/mr.2026.3.15

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