GLUKHIN v. RUSSIA JUDGMENT is whether the processing of the applicant’s personal data was justified under Article 8 § 2 of the Convention in the present case (compare S. and Marper, cited above, §§ 105-06). 86. In determining whether the processing of the applicant’s personal data was “necessary in a democratic society”, the Court will first assess the level of the actual interference with the right to respect for private life (see P.N. v. Germany, cited above, §§ 73 and 84). It notes that the police collected and stored the applicant’s digital images and used them to extract and process the applicant’s biometric personal data with the aid of facial recognition technology: first, to identify him from the photographs and the video published on Telegram and, secondly, to locate and arrest him while he was travelling on the Moscow underground. The Court considers these measures to be particularly intrusive, especially in so far as live facial recognition technology is concerned (see paragraph 37 above). A high level of justification is therefore required in order for them to be considered “necessary in a democratic society”, with the highest level of justification required for the use of live facial recognition technology. Moreover, the personal data processed contained information about the applicant’s participation in a peaceful protest and therefore revealed his political opinion. They accordingly fell in the special categories of sensitive data attracting a heightened level of protection (see paragraph 76 above). 87. In the assessment of the “necessity in a democratic society” of the processing of personal data in the context of investigations, the nature and gravity of the offences in question is one of the elements to be taken into account (see, mutatis mutandis, P.N. v. Germany, cited above, § 72). The domestic law permits the processing of biometric personal data in connection with the investigation and prosecution of any offence, irrespective of its nature and gravity. 88. The Court observes that the applicant was prosecuted for a minor offence consisting of holding a solo demonstration without a prior notification – an offence classified as administrative rather than criminal under the domestic law. He was never accused of committing any reprehensible acts during his demonstration, such as the obstruction of traffic, damage to property or acts of violence. It was never claimed that his actions presented any danger to public order or transport safety. The Court has already found that the administrative-offence proceedings against the applicant breached his right to freedom of expression (see paragraph 57 above). It considers that the use of highly intrusive facial recognition technology to identify and arrest participants of peaceful protest actions could have a chilling effect in regard of the rights to freedom of expression and assembly. 89. In such circumstances, the use of facial recognition technology to identify the applicant from the photographs and the video published on Telegram – and a fortiori the use of live facial recognition technology to 27