Police killing of Nahel in Nanterre: first elements of audio analysis

In partnership with Earshot, INDEX carried out the audio analysis of the video of the shooting that killed Nahel in Nanterre. Audio optimisation helps to make the words spoken by the police before the shooting more distinct. Some of the elements that emerge from this analysis could indicate a possible intention to kill.

On June 27, 2023, around 8:15 a.m., Nahel, 17, was shot and killed by a police officer in Nanterre (Hauts-de-Seine). A video from a witness captured the shooting, as well as the moments leading up to it. In partnership with Earshot, INDEX publishes the first elements of audio analysis of the witness video.

Audio optimisation helps to make the words spoken by the police before the shooting more distinct. Nevertheless, the analysis is in progress and does not, in our opinion, allow us to make a formal statement on the content of the oral exchanges that took place in the moments preceding the shooting.

On 3 July 2023, a journalist from France Télévision reported that “the IGPN had made a lot of progress in analyzing the video of the shooting” and that, according to its investigators, the video made it possible to hear the police order “Cut! (implied: the engine) and “Put your hands behind your head!” »

🚨 Mort de Nahel : selon l'IGPN, les policiers en cause n'ont pas crié "Je vais te mettre une balle dans la tête" et "Shoote-le" mais plutôt "Coupe ! Les mains derrière la tête". Ce serait donc une sommation et pas une menace. @infofrance2 pic.twitter.com/MFxdiFnmPx

— Telematin (@telematin) July 3, 2023

We have no more information on the analysis of the IGPN, nor of the IRCGN, than those reported by France Télévisions at the time of publication of this article. Nevertheless, in our opinion, it is impossible to establish a formal transcription of the words spoken in the moments preceding the shooting from the sole analysis of the audio tape of the witness’s video. In particular, the clear distinction between different monosyllabic words (“Shoot!”, “Cut!”…) does not seem possible from the only available audio recording, despite our audio optimization.

On the other hand, we are surprised by the transcription that the IGPN would allegedly offer of the last words spoken by one of the police officers before the shooting: « Put your hands behind your head! ». If our audio analysis is not yet definitive and does not allow us to establish a formal transcription, it nevertheless already seems to rule out the possibility that the word « behind » was pronounced before the words « the head! ». At this stage of the analysis, the hypothesis that we retain as the most probable is that the last three words spoken by the policeman are « in the head ». If this was about a shooting in the head, and it was confirmed that the sentence was pronounced by the police officer who fired the shot, then this element would indicate a possible intention to kill.

Our position is that the audio analysis must be further deepened and cross-checked with other elements in order to precisely reconstruct the course of the action.

Method

The original video audio has been optimised by suppressing low frequencies down to 160Hz, removing birdsong with iZotope RX 10 and using the spectral noise feature to filter out background noise.

Audio optimisation by Earshot, a non-profit organisation dedicated to open-source acoustic surveys.