Introduction

The process of identifying deceased individuals has crucial implications in a wide range of fields, including juridical, criminal, and civil law, as well as administrative and ethical fields1. Most significantly, it bears substantial implications for the psychological health of relatives and friends of a person reported missing, who have never been informed of the discovery of the body of their loved one ‘sous X’, hence unidentified2,3. While advancements have indeed been made in the field of unidentified bodies identification, political strategies remain an area fraught with difficulties and misconceptions4,5. One prevalent assumption is that the creation of national databases, particularly those hosting DNA profiles, in conjunction with international data-sharing agencies, will effectively resolve most, if not all, challenges pertaining to the identification of unknown bodies6. This is far from true.

Unfortunately, to date, the reality of the situation diverges significantly from expectations. From a practical point of view for those who deal with unidentified bodies in their daily work, the incapacity of national and regional systems to adequately deal with this issue is clear, due to mismanagement of several variables, ranging from scientific to administrative and legal ones1,7,8.

The issue of unidentified bodies discovered in large cities, such as Milan and Paris, poses numerous challenges, concerning reports of disappearances, the conduction of autopsies and the management of legislative requirements, as well as the right to know for relatives of missing persons9,10,11. This study can be the starting point for the development of shared practices on a supranational level that could help us find areas of commonality in this often-underestimated activity that holds fundamental implications.

The aim of the present research is to compare the experiences from the Institutes of Forensic Medicine in Milan and Paris regarding the challenges of unknown bodies and in correlating such bodies with reports of missing persons. This not only encompasses migrants but also domestic fatalities. The study further delves into a comparative analysis of the Italian and French legislative frameworks with the aim of identifying common grounds and bringing out the strengths and weaknesses of both countries, in order also to verify how and whether the right to identity is guaranteed in both countries. The ultimate goal is to propose collaborative strategies, drawing from not so diverse experiences, with a view to establish a shared approach to concretely solve the problem.

Materials and methods

This study employs a structured comparative approach to analyze the medico-legal frameworks and forensic practices related to missing persons and unidentified bodies in the cities of Milan and Paris. The two cities were selected due to their comparable roles as major forensic hubs within their respective national contexts, handling a high volume of missing persons and unidentified bodies. Both the Institute of Forensic Medicine of Milan and the Institute of Forensic Medicine of Paris have previously published data on their respective case series10,11, providing the basis for the present research. Building upon these findings, this study conducts a systematic comparison of the two jurisdictions to identify key similarities, divergences, and areas for potential harmonization. This comparative analysis was realized through the development of a structured survey aimed at evaluating forensic and legal procedures related to missing persons and unidentified bodies, as follows:

Study design

Phase 1: Retrospective comparative analysis

A retrospective analysis was conducted to compare missing persons data and previously published case series on unidentified bodies in Milan and Paris. This phase aimed to provide an overview of the magnitude of the issue in each jurisdiction and assess the medico-legal and legal frameworks governing identification procedures. Specifically, the analysis included:

  • Demographic context: comparison of population sizes, annual mortality rates, and the incidence of missing persons reports in both cities.

  • Legislative and administrative frameworks: examination of national and local legal provisions regulating missing persons investigations and the handling of unidentified bodies.

  • Forensic identification methodologies: assessment of standard procedures for post-mortem identification, including forensic autopsy, fingerprinting, genetic typing, dental profiling, and radiological imaging.

  • Data management and inter-agency coordination: evaluation of the accessibility, interoperability, and integration of databases used to crossmatch missing persons with unidentified bodies.

  • All collected data were analysed descriptively, with comparisons drawn between the two cities to highlight divergences and areas of convergence in forensic and legal practices. The findings from this phase informed the design of the second phase of the study.

Although administratively affiliated with the Préfecture de police de Paris, the forensic data utilized in this study were obtained from anonymized autopsy and medico-legal reports originally collected for scientific and public health purposes. These records are maintained by forensic pathologists operating according to professional and ethical standards, independently of police oversight or directives.

Phase 2: Development of a structured survey

Based on the retrospective analysis, a structured survey was developed to enhance the comparability of forensic procedures and legal approaches in Milan and Paris.

The survey was created by the authors in a paper-based format analysing the previously mentioned publications10,11. The survey was divided into two main sections and consisted of closed-ended questions with the possibility to comment on certain aspects that could be limited by the definitions provided in the questions. Several sections of the structured survey – particularly those related to post-mortem data documentation and procedural workflows – were informed by internationally recognized identification frameworks. Among these, the INTERPOL Disaster Victim Identification (DVI) Guide served as a conceptual reference6, as it outlines standardised procedures for the collection and comparison of ante-mortem (all information collected before death, regarding the missing persons, including biological samples) and post-mortem data (all information collected from a dead body, in order to retrieve their identity). Although originally developed for mass disaster contexts, its structured approach offers valuable insights for routine casework involving unidentified bodies.

Missing persons investigations

For Missing persons part with the aim of clarify institutional responsibilities and procedural steps in reporting and investigating missing persons, availability and accessibility of national and international databases for data cross-referencing, legal frameworks governing the search and identification process and methods for the collection and use of ante-mortem data from missing persons’ report. The questions are summarized and listed below:

  • Existence and year of establishment of national missing persons databases.

  • Criteria required for initiating a missing person search.

  • Timing and process of entering ante-mortem data into the database.

  • Roles and responsibilities for data entry and cross-referencing.

  • Accessibility and transparency of the databases (e.g., public consultation).

  • National and regional statistics on missing persons and annual reporting trends.

  • Existence of specific legislation on missing persons.

  • Legal definition and classification criteria for “missing person” status.

  • Identification of responsible authorities and their procedural roles.

  • Legal protections and procedural rights granted to relatives.

  • Existence of a mechanism allowing “right to truth” for family members.

Unidentified bodies investigations

For unidentified bodies part with the purpose of investigate standard forensic identification protocols, including primary and secondary identification methods, procedures for post-mortem data entry and comparison with missing persons databases, and financial, administrative and legal aspects of identification procedures. The questions are summarized and listed below:

  • Distinction in identification regulations between medical and judicial autopsies.

  • Existence and year of establishment of DNA and non-genetic post-mortem databases.

  • Methods for cross-referencing ante-mortem and post-mortem data.

  • Yearly and decadal statistics on unidentified bodies: received, identified, and unresolved cases.

  • Cases closed with assumed or multiple aliases.

  • Frequency and typology of examinations performed (judicial autopsy, medical autopsy, external inspection).

  • Legal or procedural provisions for autopsy in absence of judicial/diagnostic mandate.

  • Responsibility for costs incurred by examinations.

  • Existence and type of post-mortem documentation forms used (institutional, INTERPOL DVI, Ri.Sc., other).

  • Professional figures involved in handling unidentified remains (e.g., forensic scientists, odontologists, anthropologists, radiologists).

  • Roles assigned in completing post-mortem documentation.

  • Use of photographic documentation, 3D facial scanning (methods specified), and radiological imaging (X-ray, CT, MR).

  • Types of biological and anatomical samples collected for identification purposes.

  • Conditions under which dactyloscopic (fingerprint) surveys are conducted and responsible personnel.

  • - Instruments used for dental profiling (e.g., records, radiography, CT scan, cast impressions).

  • Professionals responsible for dental data collection.

  • Methods and responsibility for age estimation.

  • Storage or disposal practices for clothing and personal effects.

  • Timeframes for preservation, if applicable.

  • Frequency of identification techniques used: visual recognition, fingerprints, genetics, odontology, skeletal anthropology, personal effects, consular data, others.

  • Average time required to achieve identification.

  • Maximum time intervals recorded between discovery and identification.

  • Means through which a potential identity is hypothesized (e.g., law enforcement, personal items, social media, consular tools).

  • Standard post-autopsy outcomes for well-preserved and skeletal remains (e.g., burial, cremation, cold storage, skeletonization).

  • Procedures for long-term management of unclaimed bodies, including transfer to common ossuary or research institutions.

  • Legal and constitutional basis for post-mortem dignity.

  • Existence and scope of legal obligations to identify deceased persons.

  • Presence of an organic legislative framework for unidentified bodies.

  • Legal consequences of non-identification for relatives’ rights.

The structured survey developed in this study was not intended as a statistically generalizable instrument, but rather as a methodological tool to facilitate the comparative analysis between two case institutions.

It was distributed via email to the heads of the forensic identification teams at the Institutes of Legal Medicine in Milan and Paris, that have full access to the post-mortem records. The time to provide the responses to the questionnaire was approximately 6 months in the second half of 2023. The data were collected for a 25-years-period for Milan10, and for a 6-years period for Paris11.

To ensure accuracy, each respondent consulted individual team members with specific expertise and access to relevant data, depending on the topic addressed. In total, approximately ten professionals contributed to the completion of the survey, with seven consulted in Milan, and three in Paris. These included individuals with expertise in forensic anthropology, odontology, radiology, fingerprinting, legal procedures, and data management, who provided input on specific sections of the questionnaire relevant to their roles. These professionals, who have been working for decades on various aspects of missing persons and unidentified bodies, contributed detailed information to support the survey responses. All individuals who contributed to the completion of the survey provided written informed consent specifically for the purposes of this study. Participation was voluntary, and contributors were informed about the nature of the survey, the intended use of the data, and the publication of anonymized results.

Descriptive analysis was used to synthesize responses, focusing on recurring themes and procedural inconsistencies. A qualitative comparative analysis was conducted by the research team to identify convergences, divergences, and operational implications across the two systems. No statistical analysis was performed, as the survey was not designed for quantitative generalizability. As such, the survey responses reflect a synthesis of expert knowledge within each institution, rather than a sample-based survey targeting individual professionals. The final version of the survey was provided as supplementary material, for possible future forensic and legal comparative studies on missing persons and unidentified bodies.

Results and discussion

In order to a contextualized discussion of findings, highlighting both procedural divergences and shared challenges, results are presented alongside their discussion. Two tables summarizes the results of legislative comparison between Italy and France and the results of forensic practice analysis in Milan and Paris.

In a comparative analysis, it is necessary to start from demographic data.

Demographic and epidemiological context

Comparing the population of Milan and Paris up to 2022, distinct disparities in population counts and estimated annual deaths emerge. Milan, situated within its administrative borders, is home to approximately 1.4 million individuals. However, when considering the broader metropolitan region, the population exceeds 3.2 million inhabitants. On the other hand, the “City of Lights” accommodates around 2.2 million residents within its administrative boundaries. This figure grows substantially when considering the expansive metropolitan area of Ile-De-France, reaching over 12.4 million people. While the specific numbers vary from year to year, general estimations shed light on the annual death counts for these prominent European cities. In 2022, Milan recorded about 22,000 deaths (according to “Mortalità in eccesso negli anni 2021 e 2022 dati ufficiali dall’Italia e dal mondo” dell’Associazione Umanità e Ragione, at https://umanitaeragione.eu/report-mortalita-totale-in-eccesso-anni-2021-e-2022-dati-ufficiali-dallitalia-e-.

dal-mondo/) within the city’s metropolitan area. Paris, in comparison and relative to its larger population, has a higher estimated range of 80,500 deaths in 2022 (according to Bilan démographique 2022 de l’Île-de-France: deux naissances pour un décès, at https://www.sphinxonline.com/surveyserver/s/ccpesatisf/imageInsee2024/questionnaire.html) within its administrative borders.

Missing persons

Regarding missing persons, in 2022 slightly less than 25,000 people were reported missing in Italy of which around one fifth only in the city of Milan (1,087) and the metropolitan area. In the same period, in France between 60,000 and 40,000 people were reported missing with, in Paris and its surroundings, an annual number of 3,200-3,500 missing persons, according to a police investigation (Ministry of Interior versus ARPD). In Milan and the surroundings, in the year 2022 about 80% of missing persons were found alive (about 870 out of 1,087), 1.5% (16 individuals) were found dead and the remain (about 200) still missing, while in Paris and surroundings more than 90% (around 2,900 to 3,150 out of 3,200–3,500) of missing persons were found alive, about 2% (roughly 65 individuals) was found dead and the remaining cases (around 85 to 120) are still unsolved.

National databases and interoperability use

In Italy, since 2007 the Government’s Extraordinary Commissioner for Missing Persons (Ufficio del Commissario Straordinario di Governo Per le Persone Scomparse – UCSGPS) ensures coordination between the relevant state administrations, monitors the activities of the institutions and other actors involved in tackling the phenomenon, and promotes comparisons between national data on missing persons and unidentified bodies and territorial data. There has been the national register for missing persons Ri.Sc. (Ricerca Scomparsi – Missing Search) since 2010. This database goes back to data from 1974, which was the year they began recording such information at the Ministry of the Interior. It is only available to law enforcement professionals and allows authorized officers to insert files on missing person reports. Furthermore, under the Department of Public Security, the Police forces dispose of the Sistema di Indagine (S.D.I.), a system which allows to enter information into the Centro Elaborazione Dati (C.E.D), a database created in 1981 with the purpose of facilitating interforce communications. By accessing the S.D.I. database, the authorized operator can connect and access other databases of public administration (civil registry, motorization, for instance) and Sistema di Informazione Schengen (S.I.S.) to acquire useful information on the missing persons. The data from the S.D.I. system are then also transmitted to the Ri.Sc. database.

On the other hand, Paris and France have the Fichier des Personnes Recherchées (FPR) created in 1995. However, this dataset is not solely dedicated to missing persons. It encompasses 18 categories, including living individuals wanted by the police. Additionally, France has two more projects, FENIX (from the Police) and CADDIS (from the Gendarmerie), both holding data about both missing persons and unidentified bodies, but they are not interconnected and remain largely inaccessible to non-law enforcement professionals. FENIX, in particular, is still navigating the hurdles of getting approval from the CNIL (Commission Nationale de l’Informatique et des Libertés), which is responsible for personal data protection in France. The coexistence of the CADDIS and FENIX systems in France, while designed with complementary objectives, remains limited in terms of interoperability. This dual structure highlights underlying administrative and legal complexities, including data protection constraints imposed by the CNIL.

Italy, by the virtue of Law 85/2009, adheres to the Prüm Treaty, which calls for the creation of a national DNA databank. The central laboratory for the DNA Databank came into existence due to this treaty. Additionally, the Presidential Decree 87/2016 facilitated the establishment of a national DNA database, supported by CODIS software, operational since 2017. The Databank collects the DNA profiles of persons subjected to measures restricting their personal liberty, relating to biological findings acquired during criminal proceedings, of missing persons or their relatives and of unidentified bodies. The latter are placed in “ad hoc” section of the databank.

Already established in 1998, the French FNAEG (Fichier National Automatisé des Empreintes Génétiques) was created as a measure against offenses of a sexual nature, notably after specific high-profile serial killer cases and to protect minors. It collects DNA from offenders, relatives of missing persons, biological traces on crime scene and, since 2021, French law also authorizes the registration of DNA profiles of extrajudicial cases such as natural mass disaster and the kinship of second degree from missing persons.

Therefore, the lack of a unified national protocol further impedes integration and alignment with international initiatives. As such, the need for harmonization extends beyond purely technical aspects, encompassing regulatory, legal, and operational dimensions—levels of coordination that remain challenging even within the national context.

Operational mechanisms for reporting and investigation

For Milan, the criteria to initiate a search for a missing person are well-defined. As per the Presidential Decree 87 of 2016, specific alarming situations are prioritized. These include crime victims, minors under 12 years (except unaccompanied minors), individuals with certain cognitive or psychiatric disorders, and those with a history of violent episodes. The emphasis is placed on assessing situations on a case-by-case basis, especially for minors over 12 years. In particular, the missing person report must be filled in by the police. The information is then digitized and entered immediately into the S.D.I. system and consequently into the Ri.Sc. national database by the law enforcement agencies in charge. Also, the Ri.Sc. form (ante-mortem file) with all the information known about the missing persons, must be filled in and uploaded to the Ri.Sc. national database.

In Paris, the criteria are quite the same: vulnerable adult people with mental illness, psychological distress and high risk for suicide. On the opposite, the search for people with no alarming factors remains a serious issue for family members since they have to prove the worrying situations. In these cases, the criteria seem to be more flexible and less definitive. The initiation of a search largely depends on the willingness of the Police/Gendarmerie authorities. Such subjectivity could potentially lead to inconsistent responses in similar situations, with too many reports and too few personnel. Another common issue between Milan and Paris is that the official numbers seem to be overestimated, since there are no indications on how many reports are then retracted annually.

Further similarity concerns the presence of an interest of ordinary citizens who, through the formation of associations of relatives of missing persons (ARPD Assistance et Recherches des Personnes Disparues, in France, and Penelope in Italy) and television programmes (“Chi l’ha visto?” and “Perdu de vue” for instance) play (or have played) a key role in disseminating news regarding missing persons. In fact, even though they do not hold any kind of office or institutional role, there is a clear recognition of their role in the field of outreach throughout the country, which is also reflected in their success with the public and their concrete help in solving some missing cases.

Legal framework on missing persons

From a legal point of view, the French System and the Italian System have some comparable critical issues7,8,12,13.

In both systems, there are legislative norms aimed at regulating the search for missing persons: in Italy, there is specifically dedicated to the search for missing persons (Legge 14 novembre 2012, n. 203 recante “Disposizioni per la ricerca delle persone scomparse” – Dispositions for the search of missing persons). In France such norms are administratively provided for in Loi n°95 − 73 du 21 janvier 1995 “d’orientation et de programmation à la sécurité” – About the policy and programming of the security. Also, for minors, vulnerable adults and suspicion of criminal act, the article 74.1 from the Code De Procedure Penal states that the Public Persecutor is supervising the Police investigations.

Italian and French law differ in the definition of a missing person (a), the authorities involved in the search (b), and the protection afforded to family members (c).

(a) Regarding the definition of a missing person, in Italian legal system the disappearance is a factual condition and not a legal one. A person is considered missing when he or she has departed from his or her last domicile and whose fate is unknown, as stated in Article 48 of the Civil Code. Anyone who learns that a person is missing can report it to the police who is responsible for research activities.

Otherwise, in the French system, the law defines disappearance in the case of a worrying and/or suspicious disappearance (Disparition inquiétante)14. A key point is to understand whether one is faced with a worrying disappearance, because only if the disappearance is defined as such the Loi n°95 − 73 du 21 janvier 1995 d’orientation et de programmation à la sécurité does apply. If, on the contrary, the disappearance is not considered “suspicious”, no specific discipline is provided for and neither an official search nor an investigation is initiated. However, the law does not define in detail what constitutes a suspicious disappearance, but merely specifies that the “suspicious” nature must be inferred from the circumstances, age or state of health. By way of example, the following can be considered suspicious: departure without personal belongings; a situation of vulnerability due to age, illness or disability; the discovery of suicide letters or threats; or suspicion of radicalisation. This provision has been criticised for the wide discretion left to the public security authority in defining a “suspicious” disappearance.

(b) As for the authorities involved in the search for missing persons, both laws involve the police. The search for missing persons typically involves coordination among various law enforcement agencies, which rely on a combination of investigative methods and technological tools to locate the individual. These may include geolocation data analysis, review of surveillance footage, interviews with relatives and witnesses, and the use of national databases, depending on the characteristics of the case.

In the Italian system, the law provides only a few tasks entrusted to the authorities (Police, Prefecture, Special Commissioner) such as the collects of reports, the communication of all information on missing persons to the Interagency Data System and the National Missing Persons Search Information System (Ri.Sc.), the coordination arrangements of the authorities involved. These legislative standards are implemented by Ministry of the Interior’s guidelines that provides search activities in different phases: (1) Missing person alert and information phase (2) Activation of the search plan (3) Activation of the search unit; (4) Intervention planning (5) Management of the intervention (6) Suspension or closure of research; (7) Final report.

In France, in case of a suspicious disappearance, the police registers the missing person in the database FPR; conducts all investigations and hearings useful for the investigation and, if necessary, draws up a report or an official report. Furthermore, the police proceed with searches in private and public archives (telephone operators, banks, tax authorities, etc.). After a year of searching, if the person has still not been found or if there is no proof of death, the police or gendarmerie can issue a certificate of search failure. Until 2013, there was an administrative procedure called RIF (Recherche dans l’Intérêt des Familles) which has been suspended since legislators assumed that new technologies provided enough information for the search of missing persons. This procedure in the past allowed French police officers to conduct a series of investigation to locate the missing person outside suspicious or criminal context in the interest of families. Association like ARPD is actually the only resource for missing person families when the nature of the disappearance has not been proven to be alarming.

(c) Even with respect to the protection of family members, the two legal systems seem comparable, albeit with some differences. The Italian Law on missing persons (Legge 14 novembre 2012, n. 203 “Disposizioni per la ricerca delle persone scomparse”) does not provide specific protection for family members of missing persons. Only Ministry of the Interior’s guidelines state that it is essential that practitioners provide support to family members of the missing persons. However, the protection of family members can be derived from the rules of the Civil Code: Article 48 stipulates that in the face of a disappearance, interested parties, legitimate successors (or the prosecutor) may apply for the appointment of a curator to represent the person in court or in the administration of the missing person’s estate. In addition, pursuant to Article 49 of the Civil Code after two years have elapsed since the disappearance presumed legitimate successors and anyone who reasonably believes that he or she has rights to the property of the disappeared person dependent on his or her death may apply to the competent court, according to the preceding article, for a declaration of absence. The declaration of absence may permit, upon payment of a bond, to enter into temporary possession of the property of the disappeared person, as well as the consort may apply for the Recognition of a maintenance allowance. After ten years have elapsed since the last news of the missing person, presumed death may be declared by judgment at the request of those concerned, allowing them to enter into full possession of the property.

In France, Article 26 of the Loi n°95 − 73 du 21 Janvier 1995 d’orientation et de programmation à la sécurité provides for certain rules to protect the families of missing persons. First, the law stipulates that if the declaration of disappearance is declared by a family member, the search is immediately initiated by the police and classification as a “suspicious disappearance” is not necessary. Secondly, recognition of the certificate, one year after the start of the search, of search failure is a guarantee for the protection of family members as it proves that the person is indeed missing. It can be used, for instance, for inheritance purposes. In addition, after the certificate of unsuccessful search has been issued, the family of the missing person can ask the tutelary judge (formerly the tutelary judge) to establish a presumption of absence. This declaration allows the judge to appoint a relative of the missing person to temporarily manage their assets.

Still regarding the protection of the rights of family members, in general, it should be noted that every national legal system must respect international law from which specific protection for the family members of missing persons is inferred. The right to truth represents a pillar of the international protection accorded to family members of the disappeared. Furthermore, the European Court of Human Rights case law stated that, in cases involving enforced disappearances, the behaviour of public authorities not undertaking adequate investigations on people’s demise configures a violation of Article 3 of the European Convention (see ECtHR Kurt v. Turkey (24276/94), 1998; ECtHR Varnava v. Turkey (16064/90), 1999).

The comparison between the Italian and French legal systems highlights differences in definitions, search procedures, and the legal protection of relatives is summarised in Table 1.

Table 1 Comparative legal frameworks on missing persons and unidentified bodies in Italy and France.
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Unidentified bodies

Legal framework on unidentified bodies

From a legal point of view, the Italian and French systems are different. In particular, the two systems differ both in terms of the regulation of the protection of the dignity of the dead (a) and the legal rules aimed at cadaveric identification (b).

(a) Regarding the protection of the dignity of the dead, in Italy, there is no provision in the Constitution that expressly protects it. Rather, the protection of the dignity of the dead is a principle of legal culture that is reflected in numerous norms of the legal system such as the penal code (see Chapter II - Criminal Code, Crimes Against the Piety of the Deceased).

In the French system, the protection of the dignity of the dead has precise legal references. Article 16 par. 1 of the Civil Code, introduced by LOI n°2008 − 1350 du 19 décembre 2008, provides that «the respect due to the human body does not cease with death». The Criminal Code, Book 2, Title II, Chapter V, Sect. 4 is also dedicated to crimes against the respect due to the dead, similarly to the Italian Criminal Code.

Respect for the dignity of the dead has also been affirmed several times in case law. One may recall the famous Supreme Court ruling that the display of bodies in the «Our body» exhibition violated the respect for the dignity of the dead, guaranteed in Article 16 par 1 of the Civil Code (arrêt 16 septembre 2010).

(b) The most obvious difference between the two systems concerns the fact that in Italy there is essentially a regulatory vacuum regarding the procedures to be put in place when faced with an unknown cadaver, whereas in France the Article 16 of Civil Code and the Decree 2012 − 125 of 30 January 2012 provide specific regulations for the identification of dead bodies.

As just stated, the Italian legal system is characterized by the lack of a general obligation to identify bodies. Some obligations are stipulated in the Criminal procedure code rules (as in the above-mentioned Art. 116. disp. att. c.p.p.), that regulate prosecutor’s power during investigation.

Therefore, the autopsy is ordered only in cases where there is a suspicion of crime, or the identification of the dead is considered necessary to solve the investigation. Normally, when a cadaver without a name is found, as mentioned above, the fact that the person is not identifiable makes it a situation suspicious enough that the death be handled by the judicial authority. If the unidentified cadaver belongs, for example, to someone who died of a clear cause and therefore a natural death, the prosecutor’s office will not intervene because no crime has been committed.

In France, by contrast, there is an organic legal framework setting out the procedures to be carried out in the case of unidentified bodies.

First, Art. 16 par. 11 of the Civil Code specifies the cases in which genetic identification may be required, and in paragraph (d) this identification is provided for unidentified bodies. Furthermore, the rule specifies that the need for identification may relate to a member of the armed forces who died in the course of an operation, a victim of a natural disaster, or a missing person whose death is presumed.

The procedures for carrying out the identification searches are specified by «Décret n° 2012 − 125 du 30 janvier 2012 relatif à la procédure extrajudiciaire d’identification des personnes décédées».

With the publication of Decree 2012 − 125 of 30 January 2012, the modalities for implementing the extrajudicial procedure for the identification of deceased persons (taking of fingerprints and DNA samples, collection, storage and analysis) were regulated for the first time.

In particular, the Decree implies that persons authorized to carry out genetic and fingerprint identifications within the framework of judicial proceedings, will also be able to carry out such identifications in extrajudicial contexts, and this text puts an end to the procedure known as ‘body under X’.

In light of the analysis conducted, it is important that Italy also fill the legislative gap on this issue by identifying the competent authorities and the procedures to be carried out for the identification of an unknown body.

In conclusion, it is remarkable to remember that the lack of identification of a body can have serious consequences on the rights of family members21,22,23. The latter, in the absence of a death certificate are hindered in their access to several fundamental rights, such as those related to legal or inheritance reasons, and remain in a state of anxiety due to the ambiguous loss of their loved one24,25,26,27,28,29,30,31,32. To avoid the violation of these fundamental rights States should be obliged to provide for the identification of unidentified bodies.

Forensic procedures and resources

Delving the issues about identification of unknown bodies, in Italy, concerning autopsies, there are distinctions in identification regulation based on the type. Specifically, there isn’t a compulsory need to identify in medical autopsies. However, the scenario changes in the context of a suspected criminal offense. Here, it becomes necessary to report to the judicial authority to organize an autopsy and initiate steps for identification. This is supported by Article 116 of the Implementing Provisions of the Code of Criminal Procedure. In essence, if a death arises suspicion of a criminal act, the public prosecutor investigates and, if deemed necessary, orders an autopsy. The Mortuary Police Regulations further add to the framework. For instance, upon discovering body parts or mortal remains, it’s mandatory to inform the mayor, who then notifies the respective authorities. Moreover, cities like Milan have specific agreements in place for unidentified bodies. In particular, in 2015 a protocol was signed and concerned only few prosecutor’s offices of the Lombardy region. The same has been renewed for a larger territory in 2023 and foresees the collection of post-mortem data for every unidentified deaths in all the Lombardy region. Other Italian regions, like Lazio and Tuscany have adopted similar protocols. These regional agreements represent a practical solution to address the lack of national standardized procedures for managing unidentified bodies.

The French system also classifies autopsies into two main categories, medical and legal. Medical autopsies are mainly performed in hospitals for clinical reasons and doubt of medical liability. In contrast, legal autopsies are mandated by prosecutors or magistrates when there’s a need to ascertain the cause of death, especially in situations where the circumstances surrounding the death are doubtful. When an unidentified patient dies in a Parisian hospital, the body is sent to the forensic institute to have a legal autopsy/external examination and identification procedure performed as no medical autopsy could be done in absence of formal identityand subsequent approval of family’s members. Identification police team can also do the papillary recovery at the hospital when no external examination is requested by the prosecutor.

Even if in Italy there is no obligation stated by the law to identify unknown bodies, all DNA retrieved from unidentified bodies should be input into the already mentioned national DNA databank, as stated by the law. Furthermore, forensic experts dealing with unknown bodies are required to fill out a post-mortem form, similar to the missing persons form completed by the police, containing the post-mortem data of the corpse under examination. This form is then submitted to law enforcements to enter the information into the Ri.Sc. system and to the prefecture who sends the form to the UCSGPS to update the national registry of unknown bodies. This national registry was created in 2007 and is open to all through a keyword search (sex, place and time of the body finding, etc.). Nevertheless, a comprehensive data list remains inaccessible to non-members of law enforcement agencies. For the law enforcement agencies too, as the filling in of the RI.SC form is not mandatory, the availability of information may be incomplete.

Since 2003, the French law authorizes judicial authorities to integrate DNA profiles of unidentified bodies to FNAEG database in order to compare them with all DNA profiles registered and in absence of match, to kept them in the system for duration of 40 years. Besides this, there are databases like CADDIS and FENIX that record post-mortem information of unidentified bodies of a non-genetic nature. However, a significant challenge arises as data between CADDIS and FENIX are not crossable.

Similarly in Italy, the two databases – DNA and post-mortem data of unidentified bodies – appear to be separate. As for cross-referencing the data, while theoretically, it’s plausible, technical challenges prevent it. The Ri.Sc. System is entrusted with the responsibility of comparing ante-mortem data with post-mortem data. Also in France, the task of comparing ante-mortem data with post-mortem data predominantly falls on the shoulders of police and gendarmerie officers.

This current fragmentation of data systems illustrates the systemic challenges that hinder cross-institutional identification efforts. In this regard, the use of established international standard, such as the one by INTERPOL6,27, could serve as a blueprint for harmonising post-mortem data management across European jurisdictions. The protocol’s structured methodology could be progressively adapted for domestic and non-disaster contexts to foster interoperability and consistency in identification practices.

The operational differences between Milan and Paris in managing unidentified bodies are summarized in Table 2, with particular reference to professional roles, use of imaging and DNA, and institutional protocols.

Table 2 Comparative summary of forensic identification practices in Milan and Paris.
Full size table

Comparison of obtained data and the different casuistry between the Forensic Institute of Milan and Paris shed light on several pivotal aspects15. Between 1995 and 2019, an average of 29 unidentified bodies arrived annually at the Institute of Forensic Medicine in Milan (3% circa of all autopsies performed). From 2010 to 2019 alone, a total of 213 unknown bodies came to the attention of forensic experts. Out of these, 21 get identified each year on average, leaving 3–4 bodies unidentified, corresponding to roughly 10% of cases remaining unidentified. Some of these unidentified bodies have aliases, but those with an alias that remains unidentifiable are categorized as “pure” unknown (in detail, a “pure” unknown refers to a decedent for which no information of identity is available making it more challenging to identify or match). The pure unknown is buried as “sconosciuto”. The Milan Morgue registers the burial place of all unknown bodies. Thanks to the previously mentioned protocol, in Milan, some cooling rooms are reserved for unknown bodies to provide forensic experts with more time for identification16,17.

Statistically, around 500 bodies arrive with identification issues at the Institute of Legal Medicine of Paris annually (about 15% of all autopsies)11. Out of the 3,000 bodies received by the Institute every year, a significant majority have an alleged identity, with about 20% having no identifying elements. Regarding the bodies of unidentified bodies over the last decade, precise numbers for the entire period are not available. However, it’s worth noting that before the Protocol for UNID bodies was introduced in 2018 at the Parisian Institute, around 70 to 80 bodies were interred each year without identification. Post the implementation of this protocol, this number has reduced to about 20 to 30 bodies (about 5.6%) per year11. Police services and the Institute of Legal Medicine of Paris can indeed successfully identify between 350 and 450 persons annually. Unidentified bodies with an alias might get identified if police investigations can confirm the alias. But those with multiple aliases are labeled as “X pouvant être” (term used to describe a case where a deceased individual arrives at a forensic institute without formal – legal or scientific – identification, but with a presumed or alleged identity based on circumstantial information (e.g., personal belongings, witness statements, or contextual clues). If none of the aliases can be confirmed, they are buried under generic terms like “X masculin” or “X féminin”. The survey in Paris Forensic Institute highlights all the unidentified bodies died from natural/accidental causes, whereas all the cases without formal identity that died in criminal context were all successfully identified by homicides unit. This probably reflects the different attention provided by judicial authorities: when an offender needs to be identified, the identification of the victim is prioritized.

For bodies without an identity in Milan, procedures vary. Autopsies can be ordered either by judicial authority (about 500 cases) or for medical purposes (about 200 cases). However, external examinations are not conducted. When there isn’t a directive from an authority or a diagnostic need, autopsies can still be conducted on unidentified bodies, with costs being covered as per the memorandum of understanding in regions like Lombardy. In terms of procedures on unidentified bodies in Paris, while autopsy or external examinations mandated by the judicial authority are carried out, bodies without identity aren’t subject to autopsy unless there’s a diagnostic necessity to determine the cause of death. When these bodies are documented, an internal identification form provided by the institution is used.

In both cities, when dealing with unidentified bodies, the responsibility for completing post-mortem forms lies with medical examiners, often in collaboration with anthropologists. In addition, in the process of identification various professionals could engaged, upon the request.

In Milan, the identification of unidentified bodies involves a multidisciplinary team comprising forensic anthropologists, odontologists, dactyloscopists, radiologists, and geneticists.

In Milan, 3D facial scans and X-rays are routinely performed; also, specific samples, like hair, one or more single-rooted teeth, parts of the maxilla and mandible, IV rib, symphysis pubis, sternal end clavicle, and sections of the femur/tibia, are taken for identification purposes18. Photographic documentation and fingerprint analysis are conducted for all the bodies, and dental profiles are documented using multiple instruments (dental records, endoral X-rays, dental plasters with their eventual 3D reconstruction), primarily under the expertise of forensic odontologists. Estimating the age of an unidentified body involves evaluating the apparent age and using anthropological and forensic odontology methods. This task is commonly undertaken by forensic anthropologists or odontologists. DNA sample is always collected. Clothing and personal effects found on unidentified bodies are stored indefinitely for potential identification purposes, since they may provide contextual clues and be the basis for a suspicion of identity. The identification of these bodies usually involves multiple methods. For instance, out of 29 unidentified bodies per year, visual recognition was used for 13 (all fresh bodies), fingerprint analysis for 3, and genetics for less than 1. Other methods like odontology, analysis of soft tissues marks, skeletal anthropology, examination of personal effects through the use of magnification and scanning instruments with digital analysis, and documentation review are also employed in varying capacities. On average, identification might take weeks for high-profile cases, but for most, it spans from a month to over a year. In some cases, the identification process took place more than twenty years after the death of the individual.

After the burial in individual graves in local cemeteries, unidentified bodies were put in the common ossuary, but, since 2015, due to an agreement with some cemeteries of the Municipality of Milan, LABANOF deals with their recovery to proceed to the skeletal remains evaluation and everlasting storage. This is feasible under Article 43 of Presidential Decree No. 28 (dated September 10, 1990), which allows Universities to retrieve and collect skeletal remains that have been unclaimed for ten years following burial, solely for the purpose of academic study17.

Meanwhile, in Paris, professional figures that handle these bodies at the Institute encompass anthropologists, odontologists and dactyloscopists (the last two on request). All pathologists at the Institute have the responsibility to fill the post-mortem form, gathering the data for the file. However, all is subject to the prosecutor’s discretion and subsequent judicial authorization. The police’s special unit, SRPTS (Service Régional Police Technique et Scientifique), handles fingerprints, photographic documentation of these bodies and their personal belongings. Systematic DNA sample collection and instrumental examinations like CT scans are routinely performed on all these bodies19,20. In 2022, SRPTS documented 548 bodies and managed to identify 357 deceased individuals based on fingerprints comparison in FAED, biometric ID documents and resident permits. This is a marked improvement from 2017 when 155 bodies were documented, leading to the identification of 70 persons. The dental profile is documented through CT scans and dental scans, overseen by forensic odontologists. Estimating the age of an unidentified bodie relies on apparent age and methods of anthropology or forensic odontology, but again only if there’s a legal request from prosecutors. The process of identification typically involves various methodologies, including mostly fingerprints and genetics. On average, identification might take as little as a week for high-profile cases, but for most, it spans from a month to over a year. Since 2023, a project is ongoing to provide INTERPOL the biological data of unidentified bodies in order to be entered into the I Familia databank. Unclaimed bodies in Paris cemeteries, like the one in Thiais, are moved from individual grave to a common ossuary after five years. Therefore, there is a need to collect all samples and identification data before the burial of unknown bodies.

A further issue that both forensic institutes face is the skepticism of judicial authorities to use medical data as valuable evidence to reach a proper identification, even though population in big cities like Milan and Paris has medical files available in hospitals, clinics imaging and dental centers. In Italy, the access to dental records is particularly difficult since almost all dentists, except for very few hospital dentists in the country, are private practitioners with no obligation registering data in health care system. In Paris, since 2022, the forensic institute established a collaboration with Parisians hospitals (APHP) and the judicial authorities to authorize the access to radiological imaging registered in patient file and subsequent comparison with postmortem CT scan images.

Limitations and perspectives for harmonization

This study is based on a qualitative comparison of two institutional contexts –Milan and Paris– and does not aim to provide generalizable findings beyond these specific settings. The retrospective descriptions are based on institutional records and self-reported procedures without external triangulation, which may introduce bias or omit less formalized practices.

This study is the starting point for proposing a common reflection on European context. The structured survey was designed to enable systematic comparison between these institutions and was completed by the heads of forensic identification teams, who consulted internal experts. As such, the results reflect institutional expertise rather than individual-level or statistically representative data. Future studies should expand the sample to include additional institutions and jurisdictions and assess the feasibility of shared operational protocols and legal alignment on a broader scale.

Conclusions

In summary, in the present study, the distinct disparities in the population and estimated annual deaths between the two cities signify that Milan, despite its smaller population, faces significant challenges similar to Paris.

A key observation in the management of missing persons in Milan and Paris revolves around the database systems in place. The lack of interconnection between databases may hinder the efficient tracing and identification of missing individuals, while another challenge lies also in the overwhelming number of reports relative to the personnel available. An exception is represented by the unidentified victims of a crime, whose identity is usually ascertained in a more rapid time by the judicial authority, ensuring that no victim remains unidentified.

When delving into the domain of unidentified bodies, forensic practitioners face the same challenges since identification procedures fall under the responsibility of police and prosecutors, and in daily practice the contribution of forensic team to identification is underrated. The regulatory landscape in both cities also displays divergent approaches. Milan exhibits a more standardized approach, particularly in virtue of a Regional agreement with LABANOF. This protocol enables the systematic collection and preservation of post-mortem data, facilitates multidisciplinary forensic assessments, and ensures the long-term traceability of unidentified remains. It represents a model of best practice at the regional level, demonstrating how academic and institutional collaboration can enhance the effectiveness and continuity of identification efforts in the absence of binding national legislation.

Statistically, Paris has a more significant challenge, with about 500 unidentified bodies arriving at the Institute of Legal Medicine annually, compared to Milan’s less than 30. The introduction of the Protocol for UNID bodies in 2018 in Paris is commendable, as it has halved the number of unidentified bodies interred annually. However, with still around 20 to 30 unidentified bodies each year, there’s scope for further optimization in the process.

Moreover, the procedures for handling bodies without an identity display variation between the two cities. Milan seems to have a more extensive scope in performing autopsies, even when there isn’t a directive from an authority. In contrast, Paris seems more restricted, only subjecting unidentified bodies to autopsies/external examination when authorized by prosecutor and in addition, no further possibilities of investigation can be performed without judicial request. Furthermore, the role of various professionals, such as forensic scientists, anthropologists, and odontologists, in the identification process highlights the multidisciplinary nature of the task in both the realities. One of the pivotal findings is the diverse methods used in the identification process. In Milan, most of individuals were successfully identified (mainly through visual recognition and non-genetic techniques), while 3 cases every year remain unidentified. In Paris, the identification procedures were realized mainly through fingerprints and genetic analyses, while 20 cases every year remain with unknown identity.

Also, differences in legislative management of unidentified individuals were found, with French jurisdictions having kind of obligatory requirements and Italian lacking legal constraints. Nevertheless, despite law obligation to identify unknown bodies in France, natural/accidental deaths are not investigated the same way as homicide cases, leading to high number of unidentified cases.

In conclusion, the identification of unidentified bodies is a complex and extensive process involving a combination of various disciplines, legal regulations, advanced techniques, and specialized professionals both in forensic and judicial authorities.

Identification efforts serve both to support the families and to uphold the dignity of the deceased. Some considerable differences in the handling of unidentified bodies between Milan and Paris, and more broadly, between Italy and France, were detected. While both cities have made substantial strides in the management and identification of missing persons and unidentified bodies, there are evident areas of improvement. Adopting the positive aspects of one legislation and implementing common guidelines in Europe could have substantial benefits.

Our study underlines the need to raise attention on accidental and natural deaths as the identification procedure in those cases are not appropriately conducted: the need to bring closure to the families is the same whether the dead is criminal or not. As systems improve and databases become more integrated, there’s hope that fewer individuals will remain unidentified in the future. Harmonized legislation could improve the identification of unknown bodies, addressing a shared but contextually different challenge.

Moving forward, shared practices and a common approach could be key to handling the issue of unidentified bodies more effectively. By learning from one another, we can address this underestimated issue with the urgency and importance it deserves, particularly in a world where the missing and unidentified bodies may be from and in countries very far apart.

While this study focuses on Milan and Paris, the broader aim is to promote a framework for procedural and legal harmonization in the identification of unidentified bodies across Europe. For this reason, to move toward greater harmonisation, we suggest three concrete priorities:

  • the development of interoperable national databases that enable the cross-matching of ante-mortem and post-mortem data at European level;

  • the adoption of shared minimum standards for forensic identification protocols, including the collection of every kind of information, i.e. genetic, dental, radiological, anthropological etc. etc.;

  • the revision of national legislation, or better the promotion of a European law, to explicitly include the obligation to identify all deceased individuals, regardless of the presumed cause of death. These steps would help reduce disparities and improve the efficiency and equity of forensic identification practices.

In this regard, the INTERPOL Disaster Victim Identification protocols represent an existing and widely recognized international standard that could serve as a baseline for cross-border cooperation. Recent developments such as the INTERPOL I-Familia project represent a promising effort to facilitate international database matching, but currently this initiative seems to be not systematically adopted across all European jurisdictions. Future initiatives could explore the integration of national systems within this framework, adapting its use beyond disaster contexts to routine forensic identification procedures.