Missing Persons Investigations

Detailed data collection (preferably centralized) is essential to reconstructing the history of missing persons. This includes personal information, family history and lifestyle habits.


Police should not assume that a missing person is dead, especially in migration and conflict/post-conflict scenarios. They should make enquiries in a proportionate manner, such as checking their bank accounts or social media access.

Human sources

Missing persons investigations must be based on the principle that all families and individuals have a right to know where their missing loved ones are and what happened to them. The search process is fundamental to this right and a key component of the identification of persons alive or dead. This identification should be carried out within a legal framework that guarantees due process and ensures the quality of the investigation.

The first stage of the identification process consists in collecting background information about the disappeared persons, their families, friends and associates. This includes physical and medical profiles, lifestyle habits, associations with others, nicknames or political aliases, traces left behind by the missing persons, family relationships and personal belongings. The collection of this information is essential to understand the circumstances surrounding the disappearance and the search strategy that should be defined accordingly (e.g. determining whether the person went missing voluntarily, has been abducted by a group, etc).

This stage of the process also requires comprehensive analysis of information that is centralized, unified and coordinated at a multi-agency, multidisciplinary level. In many contexts, this is challenging because of the lack of mechanisms that allow for the transmission and exchange of information. The result is that efforts are disproportionately focused on the collection of data, leaving other important steps in the process unattended, such as preliminary investigations and the recovery and examination of bodies in case of death.

Database searches

The search for missing persons and the identification of these individuals should not be seen as a technical procedure separate from the political and social context in which it takes place. The identification of a disappeared person is not only an act of recognition reattaching an individual’s identity to a body, but also a social process – in which the family accepts or rejects the attributed identity. It is for this reason that the identification process should take into account not only the physical characteristics of a disappeared person, but also their sociological links.

Contextual information should be properly collected and recorded (ideally in centralized repositories), and its analysis should be given priority. Often, it is not analysed at all, and this prevents the identification process from being successful.

This information should cover a variety of subjects such as the geographical-temporal location, legal and administrative follow-up (habeas corpus petitions, paid press releases, etc.), the involvement of relatives and close friends in the case, information on activities of NGOs and community organizations (such as voluntary disappearances and changes of identity) as well as other relevant data on the background, motivation and cause of the individual’s disappearance.

It is important to note that the search for and identification of missing persons requires a complex operation, including the mapping of sites potentially containing human remains. The mapping of a missing person is a dynamic process that should involve both the analysis of information and its transmission, as well as the tracking of this individual’s movements in real time.


When an individual has gone missing it is important to consider that they may have left their home to escape from a situation where they feel they cannot survive and are not being well cared for. Their disappearance is a very serious issue and it is important that the police take appropriate steps to investigate it, even in the most difficult circumstances.

It is important to capture as much passive data as possible during a missing person investigation. This can include CCTV around the home address and last known location; street, aerial or satellite photography; forensic or radiographic images of the person (e.g., fingerprints or DNA samples); and telecommunication data from family members, friends, associates and partners.

Passive data can also include a person’s social media accounts, phone records, email and text messages; internet search histories; mobile application use and geo-location information. In some cases it may be necessary to apply for a warrant under the Regulation of Investigatory Powers Act 2000(opens in new tab) to access these data sources.

It is a very common practice for members of the public to contact the police with sightings of individuals who are considered to be missing. This is particularly true of high profile cases, where there has been extensive media coverage. However, in some contexts such as enforced disappearance or migration, relatives fear they will be prosecuted or incarcerated if they contact the authorities and so do not report such sightings. In such circumstances, it is important that the police consider how best to engage with these families and establish communication links in order to manage their involvement.

Video footage

The identification of missing persons involves a thorough collection of physical and medical profiles, family information, lifestyle habits and relationships, as well as circumstantial and contextual information related to their disappearance. This requires an approach that is open-minded and keeps an eye on what could be a reason for someone to go missing (for example, an elderly person travelling alone in winter might be vulnerable).

Police should engage with the media to provide the public with regular updates, but they must ensure that the information given is accurate. High profile missing person investigations can attract the interest of people who claim to have psychic or extrasensory powers, and this can put pressure on searches to be concentrated in certain areas. This can lead to police investigations being compromised.

Investigators should also consider the use of video content analytics software, which uses “in the wild” facial recognition to compare faces detected in live footage with those on digital watchlists (including still images and videos frames), enabling custom alerts to be set up. Such technology can help investigators locate and identify individuals who have disappeared, as well as identify the places they may be found in (see the figure below).

It is essential that families are involved in the investigation of disappearances, respecting their right to participate in the search for their loved ones and to be regularly informed of progress. They can offer valuable information on the background context of a disappearance, such as their relationships with local criminal gangs, and are often aware of a person’s movements and whereabouts.