“Analysis of continuity and simultaneity of audio acts and events, background acoustics did not reveal any editing or manipulation features… The audio is intact – it corresponds to the acoustic event that took place at the scene – and, thus, is an authentic evidence. The copy of file, containing digital audio recording does not introduce any distortions to the audio signal, thus the file copy can be used to establish authenticity of recorded audio, that was originally created at the scene.” This is the conclusion of expert Ivan Siparov from the Irish laboratory “Acustek” to which Bivol commissioned the examination of the longest recording in the series “Yaneva Gate”. The expert report is 17-pages long with 14 figures and can be downloaded as a PDF file here: Acustek-003-16.
Last week, the Supreme Judicial Council (SJC) closed the probe in the case “Yaneva Gate”, citing an expert report commissioned by the prosecution. The conclusion of this report was that the recordings were “manipulated”. However, the expert who came to such conclusion is a mysterious person and no one has seen the content of their labor. It is not known what is meant by “manipulation” of the recordings and whether these manipulations refer to the content of the audio information or only to its form – for example rewriting, shredding files, transcoding, etc.
Unlike the secret expertise, the expertise commissioned by Bivol has a clear origin and author. It is public and was carried out by a prestigious laboratory with a worldwide reputation. The list of the customers of “Acustek” includes the Ministry of Justice of Ireland, the Ministries of Defense and of Interior of France and the scientific police of the Carabinieri in Italy. The lab’s services in the field of audio identification and authentication are used by Romanian, Polish, Serbian, Moroccan, Egyptian, Chinese and Latvian police. The expertise is signed by Ivan Siparov, Master of Science in Physics from the University of St. Petersburg. He is the author of more than 300 speaker voice identification cases, more than 250 authenticity analysis cases, 42 trainings for Forensic Audio Examination for law enforcement agencies all over the world. He has testified in court for both prosecution and defense.
The main question that Bivol asked the experts was whether the recordings contain traces of data changes: removing or inserting audio information. Additionally, we asked to determine, if possible, the type of device used to make the recordings and whether there is confirmation of the existence of periodic markers (beeps). We provided to the experts the files that are publicly available on the platform Balkanleaks in the form in which they were received. These are eight audio files and the longest of them is 12 minutes.
The funds for the examination were collected from donations from readers of Bivol. They were not enough for the analysis of all available files from “Yaneva Gate”, therefore we opted to commission the analysis of only the longest file, which contains some of the most scandalous revelations of former judge Vladimira Yaneva.
Double and triple check
Along with the paid examination of “Acustek”, Bivol contacted other experts with a worldwide reputation in the field of audio forensic. The scientists, who examined the recordings and provided an opinion pro-bono, are Dr. Catalin Grigoras, Director of the National Center for Media Forensics in Denver, Colorado, USA and specialists from the department “Media Distribution and Security” of the Fraunhofer Institute in Germany, who did not want to be quoted by name.
Dr. Grigoras, who is one of the leading specialists in forensic audio analysis in the world, did not want to commit to an opinion on the possible editing of the content without having the original recordings and the recorder. He says that it looks like that the original recording was in WMA format 128 kbps, probably from Olympus recorder, then transcoded, something that the “Acustek” report also confirms. He confirmed that traces of periodic beeps are present, but believes that there is no scientific way to establish their origin.
Specialists from the Fraunhofer Institute, an undisputed global authority in the field of audio analysis, have also reached a similar conclusion. It suffices to say that the Institute has created the most popular format for audio compression known as MP3. According to its specialists, the recordings were initially taped in a compressed format; then they have been transcoded (and in one of them traces of the codec AAC are detected), before being decompressed in WAV format – the format in which Bivol received them
The automated analysis of the recordings, made with Fraunhofer Institute’s software platform, lasted two days and found no “traces of edits” but ” the possibility of editing that cannot be detected with conventional methods cannot be excluded,” say the scientists in their interpretation of the results.
Bivol will commission official translation of the expert report of “Akustec” and of the correspondence with Dr. Catalin Grigoras and the Fraunhofer Institute. We will then provide these documents for use by the prosecution in its probe in the recordings from “Yaneva Gate” which is still ongoing.
In case, the investigation of the prosecution is swiftly “finished” and is closed without the examination of the results of the expert report and of the opinions of the respected scientists, we will submit a new signal based on new facts and evidence of offenses and crimes revealed in the recordings that have been published after the launch of the investigation.
We remind that the content of the conversations in the recordings is fully confirmed by one of the participants in them – Rumyana Chenalova. Another participant – Vladimira Yaneva – has not denied it. Attorney Momchil Mondeshki, who, according to Chenalova, is the third participant in them, has not made any comments so far.
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