Tools and Protocols Used in Criminal Skills Related to Voice: Literature Review

Abstract

The criminal investigation aims to compose evidence to clarify crimes, and in Speech Therapy, among the possibilities of action, voice-related phonetic expertise may be one of these tools. Objective: To verify the tools or protocols used by Brazilian professionals to perform phonetic forensics related to vocal parameters. Method: Research of integrative bibliographic review from the isolated and combined consultation of the descriptors in health sciences: legal medicine, voice, criminal expertise, crimes and speech therapy in the Lilacs, Scielo, Google Scholar, Open Gray and Open Thesis databases. Results: Of 457 collections, eight were selected for reading in their entirety. The identification of a criminal through the voice has been carried out in forensic examinations since the voice presents possible characteristics of comparison, mainly the fundamental frequency, the vowels formants, the voice onset time. Registration care must be carried out so that the evidence is not excluded from criminal prosecution, being analyzed in an impartial manner. It is a recent area in Speech Therapy that lacks publications in the area. Conclusion: The resources used in phonetic forensic expertise related to vocal parameters range from the qualified professional, from different areas of knowledge (Linguistics, Speech Therapy, Engineering, Law, etc.) to the use of software that can compare the voice of different speakers. There is a shortage of literature and the practice of such practice requires interdisciplinary professional training.