Video surveillance and artificial intelligence: sanctions against a Public Body by the Italian DPA


With the decision No. 5 of 2024, the Italian Data Protection Authority (“DPA”) penalised the Municipality of Trento for the unlawful data processing in two AI surveillance projects. The DPA stated that the AI systems used did not provide adequate data anonymization techniques and that there was the lack of a solid legal basis for data processing.

Background of the case

The Municipality of Trento participated in the "Marvel" and "Protector" research projects aimed at developing technologies to enhance urban security.

In particular, the Marvel project involved the acquisition of videos from surveillance cameras and audio files from microphones installed on a public street. These data were then anonymized and analyzed using AI techniques to find possible events relevant to public safety.

The Protector project included the collection of videos and the analysis of hate posts on Twitter on YouTube to identify possible risks and threats to places of worship.


Legal framework assessed by the DPA

Firstly, the DPA deemed the GDPR applicable, highlighting the inadequacy of the data anonymization techniques used. For audio files, particularly, the technique used was the voice substitution, which did not remove the spoken content that could contain personal data. For video files, face and license plate blurring did not prevent identification through other physical characteristics or contextual elements.

The DPA stated, therefore, that the processing fell under Articles 9 and 10 of the GDPR, concerning the processing of special categories of personal data and data relating to criminal convictions and offenses. Particularly, the Protector project processed data revealing possible religious beliefs, while the Marvel project aimed to detect events relevant to public safety, potentially constituting offenses.


Confirmed violations

Regarding the principle of lawfulness of the processing of personal data, the DPA stated that there was a lack of an adequate legal basis to justify the data processing. In its defense, the Municipality of Trento based its processing on Article 2 of Regional Law No. 2/2018 and Articles 3 and 7 of the Municipality's Statute, which include, among local administrative functions, the cultural, social, and economic development of the population. However, the DPA stated that these provisions could not constitute a valid legal basis as they only assign a very generic competence to the Municipality, without meeting the quality requirements for the legal basis.

In support of its thesis, the DPA referred to the case-law of the European Court of Justice, which stated that the legislation underlying a measure which allow a data processing must provide clear and precise rules governing its scope and application. Additionally, according to the European Court of Justice, the legislation must impose minimum requirements so that data subjects have sufficient guarantees to effectively protect data against the risk of abuse.

As a further violation, the DPA highlighted that the privacy notice did not provide all the information required to data subjects. The notice, particularly, did not inform data subjects on: (i) the purpose related to a research project; (ii) the fact that the content of the recordered conversations would also be acquired and processed for the Marvel project; (iii) the data retention period.

The DPA also highlighted that the Municipality did not conduct an adeguate data protection impact assessment (DPIA) before launching the "Marvel" and "Protector" projects, that is a must have requirement for data processing like the one in analysis providing a large-scale systematic surveillance and the use of AI. The DPIA provided by the Public Body in the proceeding, particularly, was inadequate as it lacked a certain date, it was not signed by an authorized representative, and it did not sufficiently cover all data processing operations, particularly for the "Protector" project and data from "Twitter" and "YouTube." The DPIA, moreover, failed to assess the necessity and proportionality of data processing and it did not consider all the possible risks to the rights and freedoms of individuals.



The DPA ordered the Municipality to pay a sanction of 50,000 euros and banned the processing of personal data already collected within the projects “Marvel” and “Protector”, ordering the deletion of such data.



The case of the Municipality of Trento highlights the importance of strict application of the GDPR, especially in contexts involving surveillance and artificial intelligence. Public authorities, as any other data controller, must ensure that the processing of personal data using AI system is supported by a solid legal basis and that anonymization techniques are genuinely effective. This case also highlighted the stringent approach of the Italian Data Protection Authority in enforcing data protection regulations.


Article provided by INPLP member: Chiara Agostini (RP Legal & Tax, Italy)



Discover more about the INPLP and the INPLP-Members

Dr. Tobias Höllwarth (Managing Director INPLP)

What is the INPLP?

INPLP is a not-for-profit international network of qualified professionals providing expert counsel on legal and compliance issues relating to data privacy and associated matters. INPLP provides targeted and concise guidance, multi-jurisdictional views and practical information to address the ever-increasing and intensifying field of data protection challenges. INPLP fulfils its mission by sharing know-how, conducting joint research into data processing practices and engaging proactively in international cooperation in both the private and public sectors.