Police responses to cold and long-term missing person cases: a comparative study

ABSTRACT Cold/long-term missing person cases continue to be a matter of great concern for the public and police. Scholars have attempted to study the issue of missing persons more broadly, using research from across regions to understand this phenomenon. However, there has been little study of how relevant research from different regions is to other areas and little examination of cold/long-term missing person cases. Given these two considerations – these cases being of great concern but understudied and the blending of research findings from different regions – this study presents first insights on cold/long-term missing person cases from England and Wales versus Canada through a comparative examination. From this, we offer key recommendations that either region may benefit from for enhancing police response. We also highlight the applicability of research from each region, discussing the implications of different police systems, processes, and challenges.


Introduction
Over recent months, concerns have been raised about young women being murdered after first going missing, with recent international high-profile cases including Gabby Petito (United States [US], August 2021) and Sarah Everard (England, March 2021).Despite the fatal outcomes in these cases, Gabby and Sarah's bodies were recovered quickly, consistent with the widespread pattern that most missing individuals are found within one to seven days, irrespective of the outcome (Canada's Missing, 2020; National Crime Agency [NCA], 2021; Fyfe et al., 2015).However, not all missing person cases are (a) resolved quickly and (b) thought to have a particular outcome suspected during the initial investigation.It is generally recognised that people go missing for numerous and various reasons (Sedlak et al., 2002;Biehal et al., 2003;Ferguson & Huey, 2020), so the circumstances surrounding an individual's missing episode may not be immediately concerning to law enforcement officials.Often described as a 'missing continuum" (Biehal et al., 2003), individuals may "intentionally" go missing (i.e., of their own volition) or "unintentionally" (i.e., as a result of mental illness or third-party involvement) (Fyfe et al., 2015).Whether intentional or not, missing person reports always run the risk of traversing into "cold" or "long-term" cases, meaning that it has yet to be resolved despite a stretch of time passing and/or investigative leads being exhausted.Research has recognised that cold cases can encompass long-term missing person inquiries too, and as this is often at the discretion of individual police forces (c.f.Davis et al., 2014;Smythe, 2009;Walton, 2013), there is still much to uncover with this phenomenon.
The concern is how to support the families, police investigators, and the missing individual during this period of cold/long-term missingness when little academic inquiry exists into this matter, police practices and procedures can only be presumed, and the outcomes for individual cases are difficult to ascertain.In fact, little research exists on police responses to missing person cases more generally, generating substantial gaps in the knowledge base.Most of what is available stems from particular regional contexts, namely the United Kingdom (UK).While such focus is valuable for developing sound policy and practice in each region, this concentration means that current understandings are likely absent of information relevant to other areas.As well, this centring has resulted in the blending or convolution of research insights, with little differentiation or consideration for how study findings, conclusions, and recommendations from different areas may or may not be applicable.The varying regional social, economic, political, police, and public policy considerations are, therefore, not distinctly examined or weighted in the current scholarship (Huey, 2019).As an example of the differences, the regulatory and legislative frameworks for policing differ across these two regions.Mainly, criminal justice regulations and policies are federally established in the UK, whereas provincial and territorial governments form provincial policing regulations and policies in Canada.Due to the latter, Canada does not have national policing standards (Huey, 2019).
With most literature stemming from two regions, it is crucial to begin parsing how police responses to missing persons may differ across and within regional contexts to advance the scholarship.This can impact any recommendations and developments in police policy and practice, and public policy.Therefore, this study offers a comparative examination of police responses to cold/long-term cases across the regions of England and Wales and Canada.Besides offering first insights into the police management and investigation of cold/long-term cases, this serves several purposes.First, best practices and successes in each area can be acknowledged and discussed.Second, any helpful or successful approaches can be shared as learning and development opportunities to facilitate effective and efficient police investigations.Third, robust understandings can be offered on the applicability of research from either region to another.Lastly, the research base can be enhanced with insights that begin mapping regional police responses and how these may be different and similar.
A limited aspect of the currently available research from England and Wales and Canada only touched upon in some of the abovementioned studies is the police's response to missing person cases.There are two academic studies from England and Wales which are essential for outlining the police's responses (c.f.Newiss, 2006;Fyfe et al., 2015), which are to be considered in conjunction with the procedural guides available to officers (ACPO's, 2010).These studies outline the specific steps that should accompany the initial response to a missing person report and who is responsible for managing the investigation, with parallels drawn to homicide investigations if a case is deemed suspicious or with evidence of foul play.Borrowing from such insights, Canadian scholars, LePard et al. (2015), also reconstructed cases to highlight the police investigation cycle for missing persons, likening the response to missing person reports to homicide investigations while drawing upon insights from the UK context (i.e., Fyfe et al., 2015).In this way, these authors outline that the police are engaged in similar processes to criminal investigations, such as identifying, collecting, recording, and preserving information and data, and exhausting all potential leads and investigative avenues (LePard et al., 2015;Fyfe et al., 2015).However, we could locate no studies that mapped and/or outlined the elements of police responses to missing persons within and across regions.
Even less is known about cold/long-term missing persons.In 2019/20, England and Wales had 4,543 cold/long-term cases out of 320,715 missing incidents (National Crime Agency [NCA], 2021).Unfortunately, national figures on these cases are not available in the Canadian context (Canada's Missing, 2020), and such statistics are not generally offered from other regions.Ergo, the scope and extent of cold/long-term cases globally and regionally are wholly unknown.Some research is dedicated to understanding the investigation processes for these cases, primarily stemming from the US.For example, Moran (2021) offers a guide to investigating long-term missing person cases in the US, outlining five main ways cold cases can be solved: 1. Leveraging forensic science and technology, 2. Recognising changes in relationships over time, 3. Exploiting information in the correctional system, 4. Identifying investigative errors, and 5. Being persistent.Moran (2021) also details that forming a cold case unit is vital for resolving these files.Earlier work by Walton (2006) similarly discuss the police investigation of cold/long-term missing person cases from the US perspective, again likening it to criminal homicide cold cases.These authors describe critical components of the investigation response and how they are similar to that of homicide cold cases, such as investigative planning and behavioural analysis.
While these studies are helpful for cold/long-term cases intersecting with criminal matters, a substantial gap remains in the available insights on the investigation process for cases in which such information is unknown and/or the connection to criminality is not clear.Thus, a focus on cold/long-term missing persons through the lens of homicide for police responses does not account for the range of potential linkages these cases may present.The literature, therefore, cannot account for the various police response components other than connections to criminal homicide.Even still, the study of cold/long-term missing cases related to such matters is scant.
Another perspective in the literature on cold/long-term missing person cases pertains to families and friends experiencing ambiguous loss and the impact missing incidents have on the relatives' lives.One of the earliest discussions is by Australian researchers Henderson, Henderson, and Kiernan (2000), who traced the longer-term impacts of long-term missing cases.These authors highlight that effective support services for families and friends of long-term missing persons are one of the single most outstanding issues related to these cases, with it being the most significant unmet need for relatives.Specialised self-help groups for families and friends of long-term missing persons were recommended as a result (Henderson et al., 2000).Scholars have extended such findings, documenting that acceptance, emotional and social support, mental disengagement, and venting emotions are coping strategies relatives frequently engage in when a loved one is missing long term.Also discussed is that a range of socioemotional and other impacts like prolonged grief, ambiguous loss, posttraumatic stress, and depression arise for the loved ones of cold/long-term missing cases (Boss, 2006;Lenferink et al., 2019;Lenferink et al., 2018Lenferink et al., , 2017)).Ultimately, the literature concludes that cold/long-term cases have family and community-wide impacts beyond the missing individual that require specific servicing and support.Such findings further stress the importance of police responses to cold/long-term missing person cases, as their continued efforts are required to resolve such cases and/or update the loved ones of the missing.

Scope of the current study
While a relatively broad understanding of missing person cases exists in the body of literature, few studies have delved into the area of police responses, and even less have attended to cold/ long-term cases.We could not locate any research focusing on the latter from a policing perspective in the Canadian context.Additionally, no research on policing and missing persons has addressed the applicability of studies from one region to that of another but instead has blended the findings across the literature body.This study bridges these two gaps by exploring police responses to cold/long-term cases across the regions of England and Wales compared to Canada.These regions were selected given that most research in this field stems from such areas.With this, we seek to examine, in each region, how "cold" and "long-term" cases are conceptualised and what the array of police processes and policies are for these cases.Then, we identify the similarities and differences between these regions, extracting insights on any potential lessons that can be learned from either region to assist police in investigating missing person cold/long-term cases.

Data and sampling
This study draws on data from two countries.For Canada, the final data analysed pertain to 57 (n = 57) interviews with police personnel of various ranks from three provinces (Ontario, British Columbia, and Alberta).For England and Wales, data involve a seven-month non-participatory observation period with a two-force collaborative cold case unit and semi-structured interviews with thirteen cold case investigators.These data are comparable in the following ways.First, although adopting different approaches to data collection, both are oriented toward an exploratory examination of police practices and policies surrounding missing person cases that traverse into cold/long-term.Second, the same overarching question of "How do police respond to cold and long-term missing person cases?" was attended to in the UK and Canadian studies.Third, the participants included in each data are analogous: police officers of varying ranks with professional experience in missing persons work, and more specifically with cold/long-term cases.Ultimately, the focus of this study is to provide an examination of how police respond to cold/long-term missing person cases, with both approaches having to adapt to the county's approaches and chosen arrangements for such cases.The below sections further detail these data.

England and Wales
The data used in this study is extracted from a larger project which explores how police forces manage and prioritise their cold cases, including long-term missing persons, in England and Wales.Forces were recruited from an earlier stage of quantitative data collection of this project that sought to identify the prevalence of such cases, and the arrangements forces instilled for their review processes.Contact was made with the participating forces through either social media (Twitter) or the force's website contact pages.It was necessary to recruit rural and metropolitan forces to determine the review processes adopted by different "types" of forces across the country.Further context surrounding the data collection approach, justification, the participating forces, and participants can be found in (Bennett, 2020).In sum, these data presented here have been selected due to the relevance to the research questions and were generated from a seven-month nonparticipatory observation period with a two-force collaborative cold case unit and semistructured interviews with thirteen cold case investigators.
The cold case unit is staffed with nine retired officers who returned as civilian investigators to continue cold case investigations, and all have experience in major crime investigations, including homicide and missing person inquiries.The unit has responsibility for around forty unsolved cases. 1 A non-participatory observation period was chosen as it provides rich descriptions of the activities and processes of the unit (Geertz, 1973), but also ensures researcher objectivity as events are observed, rather than being participated in (Bernard, 1994;Cotton et al., 2010).The observation period was necessary to outline practices and processes associated with the reviews of both cold case homicides and long-term missing person cases, given the deficit in both academic and practitioner literature.The unit would have multiple cases under review, with investigators working independently or in small groups, and all team members would be advised of developments in weekly team meetings.These meetings allowed for updates to be shared, seek advice, generate hypotheses and new ideas, and decide on action plans for moving the case forward.During the observation period, comprehensive notes were taken to reflect case details, procedural guidance, and factors affecting the review process.
To accompany the observations, the nine members of the observed cold case unit (n = 9; Force C and D) participated in semi-structured interviews with a review officer from a large metropolitan force (Force B), two lead members of a five-force collaborative unit (Force A), encompassing both rural and metropolitan forces, and a retired cold case investigator from another metropolitan force (Force E).There are 18 identified cold case units across England and Wales, with these data presented here representing nine of these.Despite contacting 15 units, 2 responses were only received by those presented within.
All participants are referred to by an acronym.Semi-structured interviews allow a degree of structure, achieved with the use of an interview protocol, but also flexibility in participant's responses to ensure that collected data is rich (c.f.Carruthers, 1990).The interview protocol was devised initially through an exploration of the previous academic inquiry into the field and was finalised after a broader understanding was developed from the observation period.All interviews lasted approximately one hour, and participants were given the opportunity to add anything further -not covered in the interview protocol -that they felt was pertinent for understanding and conducting cold case reviews.There was a wide breadth of data collated from the observations and interviews, which was pertinent to both cold case homicides and long-term missing persons, both of which were the responsibility of units represented within this data.

Canada
Canadian data for this study are extracted from data gathered as a part of a larger project examining how police respond to missing persons in Canada.This employed semi-structured, qualitative, faceto-face and telephone interviews and an online survey with police officers across Canada.All interviews were carried out using an interview guide that covered the following topics: a) the individual's role within the police service; b) their experience with missing persons work; c) the types of cases they typically encounter and the protocols for handling these cases (in their department and individually); d) the factors that help resolve these cases, including their department's practices, policies, training, and resources; and e) the challenges they face with these cases, any encountered concerns/criticisms of missing persons work, and how these challenges and concerns should/could be addressed.These questions in the interview guide were then made available via an online survey to enhance participation rates and attenuate issues that arose during the data collection period, such as scheduling conflicts.
Participants were selected for interviews through personal social media accounts (Twitter and LinkedIn), connections, and gatekeepers.Therefore, snowball sampling was employed, and requests for police participation occurred through email and social media.This recruitment process secured 209 responses from 42 services across six provinces (Ontario, British Columbia, Manitoba, Alberta, Nova Scotia, and Saskatchewan) that were self-selected to be interviewed or surveyed.Given that the focus of this study is explicitly on cold/long-term missing person cases, any respondents that did not speak on such matters were excluded from the analysis.To that end, the final Canadian sample is of 57 interviews from the provinces of Ontario (n = 25), British Columbia (n = 19), and Alberta (n = 13). 3Thus, all survey responses were removed from this study due to an absence of relevant information.Respondents in this sample comprise a variety of roles and ranks, from Frontline Patrol Officers and Chiefs of Police, and range from six months to around 31 years of professional experience in police missing persons work in Canada.

Analytical procedure
For each of the datasets, the same analytical procedure was undertaken.First, given that the English and Welsh data involve two different forms, the notes and case details taken during the observation period, which were transcribed and initially organised according to the cases discussed-as per the structure of the team meetings-were combined with the transcripts from the semi-structured interviews.Simultaneous analysis allowed these data to be refined to triangulate the two stages of data collection (Denzin & Lincoln, 2008).
Then, both datasets were thematically analysed following the recommendations by Braun and Clarke (2006).Thematic analysis is a flexible approach to qualitative research that allows for a rich account of respondent perspectives through uncovering the differences and similarities across and within participants (Braun & Clarke, 2006).Initially, the responses were read, and notes were made about some of the initial codes surfacing (also called "candidate themes"), which are the most basic meaningful semantic elements of data.Guided by inductive reasoning, codes were then sorted and grouped based on similarity, and analogous codes were combined to form "overarching themes" (Braun & Clarke, 2006).At this stage, each preliminary overarching theme was reviewed based on internal homogeneity and external heterogeneity (Patton, 1999), as well as the extent to which these themes related to the datasets captured as a whole.Then, the overarching themes were named and defined.Following this, these data were analytically coded and sorted based on these themes, and then quotes illustrative of each theme were extracted and organised.The below section presents the results of this analytical process.

England and Wales
Of the 2,543 unsolved homicides in England and Wales (identified in the larger project; c.f. Bennett, 2020), 44 long-term missing person cases fell under the umbrella term of a "cold case."Seven (1.7%) of these cases are the responsibility of the police forces who participated in the larger project, and references to these cases are included throughout the analysis where appropriate.However, a discrepancy was highlighted whereby some of the participating forces were reviewing more of these files than what they disclosed in their official number of unsolved cases.The reasons for this were two-fold: firstly, it helps to keep the number of unsolved cases attributed to each force low, and, secondly, it avoids assumptions being made that these cases are now considered homicides.While problematic for ascertaining the true prevalence of these cases, the participants highlighted different trajectories that these cases may take, determining whether they are to be included within a dedicated Cold Case Unit (CCU) or if they remain with the Missing Persons Team (MPT).It will be highlighted, however, in the forthcoming sections that there are discrepancies when allocating or pursuing cases following these trajectories.These data used for this analysis was from the perspective of dedicated CCUs across England, and so whilst their focus is on homicides, their remit extends to long-term missing person cases.

Managing long-term missing person cases
To facilitate the management and investigation of long-term missing person cases, police forces have the ACPO (2010) procedural guide, and a flowchart of the investigative processes are provided on the College of Policing's (2020) website.This document and flowchart provide advice for investigators once missing person cases become "cold" and highlight the importance of the reviews to be undertaken.It is recommended that all missing person inquiries that are not resolved after 28days should be subject to review by a Senior Investigating Officer (SIO) with experience in complex, long-term inquiries (ACPO, 2010;College of Policing, 2021).
"If someone went missing today and they are classed as high risk, they [police force] might ask us to get involved at an early stage, within the first few days to sit down with them" (Simon, Force A).
Whilst Force A focuses on the reviews of cold cases for five different forces, they can assist with ongoing missing person inquiries that run the risk of becoming long-term and take responsibility for the 28-day review.Simon emphasised that their purpose was to "give a direction and guidance to the staff" with the hope of resolving the case.All participants within the CCUs participating in this study have experience in conducting and leading complex inquiries.The experience of participants may make them the most appropriate unit/persons to conduct the 28-day review, in line with the recommendations from the ACPO (2010) policy.
However, the policy does not outline what the review should consist of, and this is not something explored within the currently available literature.Nevertheless, the purpose, remit, and effectiveness of 28-day reviews are discussed within the homicide literature (c.f.Jones et al., 2008;Nicol et al., 2004).It is assumed, therefore, that the underlying principles of the homicide reviews are implemented for long-term missing persons.Should the review at 28-days not lead to a resolution of the case, the policy dictates that further reviews are to be conducted at 3-, 6-and 12-months (ACPO, 2010; College of Policing, 2021).Once a missing person inquiry has undergone these reviews, it was recognised that the case would be subject to annual reviews: "Cold case reviewing is not about did they leave any holes, did they leave something out, did they not do something . . .as part of the review, there might be something that they should have done . . .you might have something jump out at you and you think 'bloody hell'" (Kyle, Force D).
The purpose of the CCUs in these inquiries is to ensure that all investigative opportunities were fully exploited during the initial investigation, managing risk for the individual or person who may have caused them harm, and resolving the case.Simon (Force A) details this, "That's what we're about, getting a resolution.Whether it be a missing person and finding them alive."While the management and investigations of cold/long-term missing person cases are not clearly articulated in policies, the participants did identify two trajectories that cases can follow, which provides insight into their management and investigations after 12 months, which appears to be the time boundary for when the cases are closed down as "active."

Trajectories for long-term missing person cases
Forces C and D highlighted that while they may take responsibility for a long-term missing person inquiry, the reasons are not always clearly articulated or justified."Alex [head of the CCU] allocating it?It's as simple as that really" (Michael, Force C).This ad-hoc approach to allocating cases was apparent across all participating forces, even if the trajectories identified below are implemented in these forces.The first trajectory, which is touched upon in the procedural guide (c.f.ACPO, 2010), is that the case remains the responsibility of the MPT once it is 12 months old and it is subject to annual "proof of life" inquiries.There are many tools available to the Missing Person to facilitate these inquiries: "We've got Call Credit, Find my Past, Scorebook, Experian, and they're quite good research tools for finding people and finding witnesses and complainants even from jobs" (Michael, Force D).
By using these tools, in conjunction with the police databases, officers are attempting to identify whether the missing person has had police contact in another jurisdiction, admitted to hospital, opened a bank account recently, sold or bought a vehicle, or used any of their existing accounts (i.e., banks, phones, social media accounts).The annual "proof of life" inquiries should also ascertain whether any new information from witnesses or members of the public have been reported.However, officers within MPTs managing a long-term missing person should seek to action any new information as and when it comes into the force.An assessment is made of this information to determine its impact on progressing the case and sometimes whether the case should become the responsibility of a CCU.The passing of a long-term missing person case to a CCU is the second trajectory for these cases across England: "Because this information came in from a member of the public with this, you know, I've been hanging onto this, it's obviously been mentioned in the community for years around [missing persons name], but it's never been passed on to look at really . . .And then when you actually look at the missing from home investigation, you think 'God, why didn't someone pick this up years ago'?But we still haven't got to the bottom of that" (Kevin, Force C).
The two trajectories are identified within Table 1 and indicate the investigative activities which detectives must adhere to when assuming responsibility for long-term missing person cases.
For one case, referred to as Op.Saltmarsh here, a young man disappeared from a rural, seaside location in Northern England nearly 30 years ago.At the time, significant effort was made to locate the individual, but to no success.Approximately 2-years ago (just before data collection started), a lady rang the police to check on the progress of his case and to share some information that had been circulating in the local community after he had disappeared.When the lady provided the information, it was passed between several departments before landing with the CCU.Initially, it was unclear as to why they had assumed responsibility for the case, but a preliminary review justified it staying within the CCU for a more intensive review than just proof of life inquiries.
"Who came to us and said, look this is what we've got and so this is worth looking at, I mean it absolutely stinks to high heaven, and Alex said 'yeah, take it on'" (Kevin, Force C).
Initially, participants within Forces C and D spoke of the risk classification assigned to cases that may determine the trajectory that a case follows: "I mean, nowadays he would have been flagged up as a high priority without question, and they would have put a lot more effort into it I think, but looking at it, I can't believe it was left as it was" (Kevin, Force C).
For Op. Saltmarsh, the initial risk classification was inappropriate and did not accurately reflect the circumstances of the disappearance or the mental capacity of the individual.Thus, once the CCU began their review of the case, it was determined that a more intensive investigation should • Monitor victim's social media, bank accounts, and phone records.
• Trace individuals through media appeals, searches, and information from witnesses.
• Update the family on proof of life enquiry results.Active: Cold Case Unit (CCU) 1. Establish Terms of Reference to guide the review's parameters and purpose.2. Determine focus of the review to be undertaken.

Identify persons of interest, or with
knowledge of the victim's whereabouts.
• Verify all lines of inquiry were pursued.
• Identify new lines of inquiry.
have been had and that the CCU was the most appropriate team to do this.However, the CCU for Force C and D would also take responsibility for cases that were not initially, or following a subsequent review, deemed such a high priority.
"I mean, we have been given other missing from home cases as well . . .she was a refugee who went missing . . .I've got it for review again, and that was probably 10 years ago I think, and that's only been looked at once . . ." (Kevin, Force C).
For this case, the initial investigation and subsequent review (undertaken ten years previously) did not indicate a high concern for this individual's safety following their missing episode.The reason that the CCU took responsibility for this case is that it is long overdue for a review, and they have been deemed the team with the capacity to conduct it.There was, therefore, no particular reason for them to take responsibility for this case, and given the policies and procedural guides outlined above, this is a case that would -most likely -have followed the first trajectory and stayed with the MPT.These experiences indicate an ad-hoc approach to managing long-term missing persons and determining who will take responsibility.It was also identified that the decision for the CCU to manage the review of a long-term missing person case might be made by senior management, and while it may not be immediately apparent as to why the trajectories may sometimes explain a CCU's involvement.

Including cases within CCUs
A further discrepancy noted is the age of the case and when it should follow the second trajectory and become the responsibility of the CCU.As the participating forces take responsibility for all cold case homicides within their force area, they adhere to the Murder Investigation Manual's (ACPO, 2010) two-year time boundary.For long-term missing person cases, it appears that 12 months is the accepted time for recognising a case as "cold," in line with the procedural guidance (ACPO, 2010).Michael (Force D) discusses this, "I don't think we would pick anything up that was only a year old.I think we've got a lot of other things before we would go to something that is a year old.Maybe that's for bigger forces, I don't know."While Michael acknowledges that 12 months is too soon to accept cases into the CCU, with the availability of investigative lines of inquiry still an option to pursue, the responsibility for cases during this period is unclear.As with Op.Saltmarsh, discussed above, there is a concern that cases may fall through the gaps during this time though.
"This is about managing risk as well . . .if I get three weeks into a job and think 'bloody hell, we haven't done this', then that would be an interim report, review" (Kyle, Force D).
Another concern raised by some participants was the use of terminology and case classification for its impact on pursuing cases appropriately and managing risk.Given the ad-hoc approach to assigning cases to the different trajectories, and namely into the CCU, it becomes imperative to clarify the circumstances of the case to ensure that the appropriate investigative response is given.For Forces C and D predominantly, they will change their risk classification from a long-term missing person to a suspected no-body homicide, if the circumstances dictate.
There are different approaches required for conducting reviews of no-body murders in comparison to cases with a body.
"Quite unusual as we'd examine a cold case not knowing the suspect, but actually knowing who the suspect is . . .yes it could be other people but actually it's overwhelming" (Paul, Force D).
For one of Force D's cases, they have a lady missing for over ten years, and her partner at the time was subject to covert intelligence tactics given his suspected involvement in drug operations.The lady's disappearance was spoken of, in loose terms, during the covert intelligence collection.Whilst convinced that there is a fatal outcome in this case, and thus it is considered a no-body murder, the force has experience of such cases.This may make them suitable to review long-term missing person cases in light of having no resolution or a body (if applicable given the circumstances of the case).
"If you haven't got a body, then your whole case is potentially based on extremely good circumstantial evidence and it is who the most likely person to be responsible for this crime . . .and all of this comes from victimology" (Jane, Force D).
Jane emphasised that victimology is essential for all cases, and their progress, particularly when there is no body: "It tells you the story of this person's life and it's about putting the case together with as much as you've possibly got, and some people may say 'well if you haven't got the forensic link then you've got no case.'So, do we give up then?"As with all cases, irrespective of the classification, forensic evidence and its advances over the years have been an important determinant of case prioritisation and resolution.It is not always a suitable line of inquiry for long-term missing persons, however, thus necessitating the need for a different mindset and approach.
In the UK, the available procedural guidance suggests that whilst a cold case review of a longterm missing person case may be a possibility (ACPO, 2010), the guidance on cold case reviews prioritises forensic evidence advances and applications (ACPO, 2006).Police forces are encouraged to retain any forensic evidence obtained during the initial investigation of a missing person (College of Policing, 2021), but the purpose of this retention is for identification, presumably for any remains.Thus, the purpose of subjecting these files to cold case reviews -given the forensic evidence focus -is not clear.Individual forces have adapted to this minimal guidance and focused on the presentation of the case."It's very important in the way in which the summary of evidence is presented . . .it's a perfectly adequate summary . . .if a QC had read it, that summary, or even re-tweaked it or re-presented some of it, they would have taken it as a no-body murder" (Paul, Force D).
For these cases, the CCU focuses on creating a firm narrative surrounding the circumstances of the individual's disappearance, which may warrant re-classification to a no-body homicide but may also help clarify events surrounding the case and ensure that an appropriate risk classification is afforded to the case.Forces may be reluctant to use the classification of "no-body" as this will (a) increase their number of unsolved cases in the officially recorded statistics, and (b) require a more resourceintensive investigation.
A prominent issue raised by all participants was challenges with resources, particularly surrounding insufficient personnel to manage the number of cases that they are responsible for, which impacts on their ability to pursue investigations.As an example, Caroline (Force B) discusses, "When you've got 198 cases and there's only three of you, the honest answer, it's not possible, it's not possible."From Force B's perspective, they are unable to review cases every two-years, as per the ACPO ( 2006) policy, because they do not have the resources available.Further, they will only review cases that are determined, during the initial investigation, to be no-body murders.The lack of resources across all forces impacts how far they can pursue cases: "Some forces, where it is so busy, they will only have a very limited amount of time to get a result.They can't go on forever.You would never have got [redacted] case going on as long as it did in most forces because you just wouldn't have been able to do that.yes, you would have still worked on information, but you wouldn't have had the luxury of pursuing it like that because other stuff is also coming in and it's a matter of prioritising" (Nick, Force D).
Whilst discussing a high-risk and very high-profile long-term missing person case in their force area, Nick discussed how it is not possible to pursue all cases for such a long time in every force.This case did remain "active" for a long time because it was high profile and there was a lot of public interest in the case.The force, subsequently, were given a lot of information about the case and though it was felt, at times, that they could not see "the wood from the trees" because of the leads generated, it warranted the case staying "active" for longer.But, given how costly missing person inquiries are (c.f.Shalev Greene & Hayden, 2014), and the priority of high-risk cases continuously coming in, there is a need, recognised by participants, to draw a line in the case and focus attention and resources onto other inquiries.
"It can't be a one size fits all, you know, I think you've got to accept that once a job gets older, it won't get looked at quite as strictly as those . . .and you've only got finite resources you know, we're not a big team" (Simon, Force A).
A consideration for the participants, irrespective of the trajectory taken for the case, is the importance of liaising with the victim's families and ensuring that they understand how their loved one's case will be managed and investigated once it has become a long-term inquiry.
"I'd see . . .families of victims . .., and I would tell them, 'I'll be honest with you, all we are allowed to do is review the case, and we have very little . . .' . . .But every time without exception, when I have done that people have that 'thank you' as I was the first person ever to be honest with them.You're explaining the process and they can trust you, even if it is not perfect" (Henry, Force E).

Defining "cold" and "long-term"
There emerged no clear conception of what constitutes a case as "cold" or "long-term."Instead, the definitions are that which the agency or each officer designates such to be, and there is no universally accepted designation."Cold" appears as the most frequently used.Police generally assign this to a case when all investigative avenues and techniques (e.g., leads, exhibits) are exhausted, and the individual is still not located or returned.Or, as Officer 4001 (Missing Persons Coordinator) exclaims, "when everything has been done that could be done."Officer 3004 (Historical Case Detective) further states that cold cases are "when we have no other investigative tactics to use and all types of oversight and review find the same that there's nothing more that can be done in that moment.When this happens, we don't close the cases, they just go dormant, cold." Turning to "long-term," this surfaced as an ambiguous classification.Some police agencies and officers assign a certain amount of time needing to pass to be "long-term," others use this label with "cold case" interchangeably, and the remaining do not use it.To illustrate, Officer 5002 (Missing Persons Coordinator) states, "I mean, long-term cases are just cases that stay open long-term.There's not really any other way we think about them, but it's just me overseeing files and noticing they've been open for quite a while."Whereas Officer 1001 (Major Crimes Investigator) acknowledges that, in his agency, "files that had been open for two years or more are long-term cases" or Officer 5003 (Detective) notes there is a "90-day mark."This said, most participants discuss that time should not be a consideration for categorising these missing person files.For instance, Officer 14007 (Detective, Missing Persons Unit) expresses, "No, it's not at all considered . . .We have some cases that are pretty recent, but there's quite a bit of evidence to suggest that they've died, whether it be missing like hikers or a file that we believe that the person may have committed suicide, but we can't locate their body.It's just that every investigative technique has been exhausted."Generally, though, to be regarded as cold/long-term, police agencies in Canada weigh or consider the investigative state, time passed, and/or situational incidents of the case.A quote from Officer 5003 (Detective) exemplifies this best: "if you were reported missing, you'd be long-term 90 days later, maybe sooner if foul play is suspected, or if the investigator figures something is going sideways."

Police responses to cold/long-term missing person cases
No response system to cold/long-term missing person cases exists across and within the Canadian agencies sampled, nor was there any form of a procedural guide like what the ACPO establishes in the UK.Instead, respondents expressed that they were unsure of the processes for these files at their own agency and beyond.Many emphasised that the most apparent component of police responses to missing person cases is the initial and "active" investigation and search, primarily within the first day or several days following a person being reported missing.After that, when cases traverse into cold/long-term, it appears to be a major question over the trajectories of the case with respect to who/what area is responsible for any further response efforts and, generally, what is next.Officer 7009 (Detective) plainly remarks "we don't know what to do with cold cases most of the time."Notably, Officer 11007 (Missing Persons Coordinator) discusses why this may be: "I think the continuity, or lack thereof, is the biggest problem that we have with these cases.Like, we have a clear understanding of what to do with missing person cases upfront, but after that, our process is considerably in the grey zone.There isn't much or any structure."Resulting from this is some respondents attributing the resolution of the vast majority of cold/long-term cases to be as a consequence of happenchance, or "by luck or by clock" (Officer 8001, Chief).
Nevertheless, a few approaches repeated across the Canadian data.First, regarding who/what area is responsible for cold/long-term cases, when investigative avenues and techniques are determined at an end, the first trajectory is that of some organisations transferring the case to be managed by dedicated, specialised personnel and/or units.Examples of these emerged as a Missing Persons Unit, Missing Persons Coordinator, or Historical Case Detective.This occurs to engage police personnel with the necessary skills, knowledge, and resources for quality control and ensure oversight for consistency in later responses.As Officer 4002 (Frontline Patrol Officer) discusses, "Well, there's nothing in policy.But the people that went missing and were just never found, they're like long term missing persons, with suspected foul play or suspicious nature, those investigations are with the major crimes section.Many open files, I'm sure you'd be aware of some of them that are high profile cases, are unfortunate.Those are circumstances that need to go into the major crimes investigative realm who are qualified to investigate serious crimes.It's another layer of seriousness." In the absence of dedicated units or personnel, or an assessed lack of need for the case to be provided such resources (i.e., due to little time passed or the situational case characteristics), the second trajectory involves files tending to stay with general duty investigators or "plainclothes" officers to be worked on "off the corner of someone's desk" (Officer 4003, Deputy Chief).In these situations, participants remark that these files often end up "falling through the cracks" and receiving "little follow-up or attention."Officer 7007 (Detective) details this, "Once we've done all we can for the case in terms of the initial investigation part, the file goes into cyberspace and awaits to be assigned to someone else.This can take time.Even when it's assigned to someone, they can be on vacation, or involved in other pressing duties, so it gets left in limbo."Officer 15006 (Staff Sergeant) also notes how this occurs in his agency once assigned responsibility for the case: "As one of the investigators for these cases, I can say that if we're assigned to one of these files, we just work until we figure it's time to stop.Although, really, this depends on the person the file is assigned to.If they're diligent, they'll keep going, but otherwise, the file is put on ice."The majority of included organisations follow this approach due to police agency resources and the priority of these cases.To note, no sampled organisations surfaced with a Cold Case Unit (or CCU) that exists to work on missing person files, so this trajectory does not emerge in the Canadian context, unlike in the UK.Although one officer mentions that their organisation has a CCU, he notes it is for generally crime reports, and does not typically handle missing persons.Instead, cold/long-term missing person files are managed by the Missing Persons Coordinator at this agency.
The "what is next" involves the following: 1) administrative response, 2) passive response, and 3) active response (see, Table 2).The administrative response is considered "solving cold cases from our desk," as Officer 16011 (Missing Persons Unit) states.This typically requires dedicated staffboth civilian and sworn -within the agency concentrating on cold/long-term missing person cases.Responses such personnel tend to employ are, in no particular order, 1. case review, 2. case updating, 3. building rapport and communicating with the families of the missing, 4. connecting with services, organisations, and others alike, and 5. entering file information into any new or updated programs or services.General duties or "plainclothes" investigators engage in similar tactics, yet on a lesser scale/to a lesser extent due to less time at their disposal, availability away from other responsibilities, skill and knowledge, connections and rapport, and resources.
Case review and updating emerged as one of the more arduous but necessary responses to these files.This first includes locating any original documents and files pertaining to the case.Manually going through every part of the file to verify all avenues and techniques were previously fulfilled, all forms and information are completed, and creating a plan for the next steps in the response are key parts of case review.That is, this step in the process entails not only file review, but also generating an investigative plan.This requires officers to impute any information on paper into police digital data and record management systems, including transcribing notes (of which sometimes have deteriorated or been damaged), scanning modes, and systematising filing systems.Through this, gaps in the response and investigative leads can be identified for management and response.Respondents take note of distinct challenges with some files with respect to this process, given that many are on paper and scattered in boxes with no organisation system or categorisation/ labelling.For instance, when discussing a high-profile cold, missing toddler case, Officer 19003 (Missing Person Coordinator) observes that "it's been going on since the 60s and, because it's been highly publicized and talked about and it had a tip line, we got so much information . . .All of its files take up a full room.There's over 130 banker boxes filled high with notes and leads and case information that I'm working on getting digitized and going through . . .But I can't even read some of them, some are stained, the ink has even faded or is even completely gone on some pieces of paper." Case updating entails bringing the files to current-day investigation standards to address any developments, adjustments, or differences in policy and practice and establish that they contain upto-date information, or, if they do not have recent details, going through the process of gathering any needed particulars (e.g., from the family).This means searching and reviewing all of the previous investigative steps taken and investigating any responses missed or as a part of newly introduced processes that were not present at the time of the initial or active investigation.Participants note that this also ensures check-ins and conversations with the families and friends of the missing.To illustrate, Officer 3004 (Historical Case Detective) stresses that, "Before 2007, for example, family communication wasn't really valued in the investigative process.So, one of my main tasks is bringing this up to standard.Family communication is massive.There was a failure of communication pre-2007, so police failed the family.It's super important to collaborate with the family to show that the police are trying, really trying to get new information.It's also important to connect with family to get consent to run new ideas by them for looking at the case and get DNA for new databases for example.I try to keep them updated every three or so months but only if the family would like.This is a huge part of our response, if you will, to these cases."• Locate original documents.
• Verify past investigation techniques were fulfilled.
• Create future investigation plan.
• Bring files up to current-day standards.
• Frequent contact with the family of the missing.
• Connect with coroners and medical examiners.
• Public reporting details from sightings or appeals.
• DNA match on national DNA databank.
• Dental match on dental database.
• Publish story with news sites.
• Follow-up on leads received from passive response and appeals.
Respondents remark that making certain that all cold/long-term cases are up-to-date is essential to "set up the files for success for possible identification down the road" (Officer 18013, Investigator, Major Crimes Unit).Officers engaged in administrative response make a point of case review and updating consuming the greatest amount of police response efforts, particularly to try finding any amount of guidance or evidence that can generate a lead or leads.
Connecting with services, organisations, and others emerged as critical for collaboration and information sharing across and within sectors in efforts to resolve the case.These include, but are not limited to, coroners, medical examiners, and social and health services.For example, as one participant notes, "I have annual follow-up with the national dental bank and with the coroner . . .I also phone all the hospitals, all the care homes, see if they've had anybody else walk-in or get dropped off that could be one of my cases a couple of times a year or when I hear about their cases through [my connections]" (Officer 4001, Missing Persons Coordinator).Relatedly, participants discuss roping in other personnel and specialised units from within their agency and other police agencies based on features of the case for additional help and support, such as the homicide division if there is evidence that a criminal homicide has occurred or another police organisation if the case is linked to their jurisdiction (e.g., family in the area).Thus, administrative responses involve building rapport and connections with local and regional key stakeholders, and other police personnel and units, to engage in case review, updating, and resolution attempts.
Lastly, this also concerns the continued search for and engagement with new tools, techniques, programs, and services.Respondents identify a number of these, such as adding files to Canada's Missing database for missing persons and unidentified remains, the Royal Canadian Mounted Police (RCMP) cold case files database, dental record registry, provincial and national DNA databank, fingerprinting, coroner's programs like Missing Person Query, 4 and age progression programs, among others.As an example, Officer 3004 (Historical Case Detective) discusses the newer provincial DNA database in their region: "It's run by the RCMP.It centralises and streamlines the DNA process for missing persons, meaning that uploading DNA here will make it accessible nationally.Like, it matches DNA nationally and provincially." Outside of administrative efforts, participants note that police responses involve "passive" investigation techniques as the file is treated as "inactive" (Officer 2001, Staff Sergeant).What is meant by this is that in the absence of a structured or clear response system, resolving cold/longterm cases generally appears to be in a state of suspension and reliant upon waiting on information being brought to the police from two fronts: the public, such as by way of call-ins with information on sightings and potential connections, and institutions, programs, and services alike flagging the missing person and alerting the police, such as DNA or dental programs locating a profile match.Regarding the latter, this emerged as including some forensic investigation elements.As Officer 8003 (Investigator, Missing Persons Unit) explains, "[We] contact biological family members, so parents or brothers and sisters of the missing person, and [we're] supposed to obtain a DNA sample from those family members.Either a blood sample or a saliva mucus swab.
[We] collect the missing person's original dental information from whoever the dentist is.If fingerprints are on file for a missing person, for example, many years ago, they were charged with a crime or something and they have a criminal record and their fingerprints are on file, or they applied for a job or something that required their fingerprints, police are supposed to request those fingerprints.[We] also collect photographs of the missing person in the best resemblance of the person when they went missing.Those four things-DNA, dental, fingerprints and photographs-are used by the police to positively identify unidentified human remains or to identify missing people when they're found." Relatedly, participants discuss that there needs to be some form of open communication with the public about these cases, and about how people can get in-touch with the police if any information comes to light.Officer 12001 (Sergeant) outlines this, "You need to open up avenues where it's okay for people to submit information and tips . . .It is rare but sometimes you'll get tips about ten years later.Or you get the ever popular found human remains call where someone's walking their dog and they've dug up a human femur which happens and then we get called out and then you have to backtrack and figure out which missing person is it actually relating to.But if you don't have that mechanism or opportunity for the public or whatever, then you're just simply not going to get that information."Therefore, passive response pertains to the waiting for information to emerge through a variety of mediums, which requires systems in place for open communication channels with the public, community groups, and other services, along with the necessary units, personnel, and/or other resources to respond and attend to such tips and leads.This did not emerge as response-driven or proactive, but instead is a "stand-by" approach.
Finally, participants outline "active" investigation techniques across the sampled agencies: media and other public appeals, and the following of leads.Police callouts for information were stressed by participants as of high importance to bring attention to the case and try to enlist the help of the public.This was likened to "reactivating" the case and raising it to an "investigation" status by several officers.Respondents discuss that they push these appeals through a variety of mediums, including news sites and their organisation's social media pages (Twitter, Facebook, Instagram).Also outlined is that some families and friends, in collaboration with the police, will hand out posters and flyers around areas in an effort to generate information and leads on cold/long-term missing persons.As a case, Officer 11002 (Missing Persons Coordinator) discusses one missing teenager case from the early 1970s recently in news stories: "It's been in the media a lot recently.It's just one of those cases that, for whatever reason, probably because we're in the era of the new information age and internet and all that kind of stuff, Twitter, you name it.We have just got hammered with information from the public, which is great, everybody is trying to help the best that they can . . .So, it's many, many avenues, tons of investigations, still tons of outstanding avenues you get.And that's why we call it active even though it's a long-term case.And it's why we do these appeals." Accordingly, respondents highlight that engaging in media and other public appeals, with the family's consent and/or participation, often revives the case, generates new investigative avenues and leads to be followed up on, and adds information to the file that may be of use for resolving the case.This said, there emerged no system or process for selecting when and which cases are publicised or "reactivated."Instead, active investigation efforts were often arbitrarily conducted.
Most participants discussed frustration with trying to engage in any active investigation efforts, which may explain why such attempts are typically at-random.For example, Officer 8001 (Chief) explains that "you don't have an avenue to chase, right?It's not like a homicide investigation where you're building that victimology and you've got potentially a suspect, or you've got some DNA.I mean, it's unlikely that you're doing all of that with these files, because you just don't know, and all our information has come up dry.So that's the more frustrating part with pretty much all cold cases."This is mirrored by other respondents, such as Officer 17004 (Major Crime Investigations) noting that "we typically don't have a starting point with these cases, which means we can't begin any investigating, and then no place to go after that."Therefore, the challenges with these cases appear to impede active investigation efforts.It is then unsurprising that most police responses to cold/long-term files are primarily administrative and passive endeavours, depending upon many factors like the person(s) or unit(s) the file is assigned, the features of the case, and the number of other duties needed to be attended to.

Discussion
This study aimed to gain insights into the police management and investigation of cold and longterm missing person cases in England and Wales compared to Canada.This occurred for three reasons: 1.Little is known about police responses to missing person cases, 2. Scholarly examination of police responses to cold/long-term cases is virtually non-existent, and 3. Research on missing persons and policing frequently uses insights from across many regions to explain the phenomenon of missing persons, blending research findings, conclusions, and recommendations from areas with distinct and different resources, policing systems, and public policy.Layering these matters produces substantial literature gaps, which this study sought to address.
Given that our data was taken from different participant's perspectives (the roles and units that they work in) which are important to note, similarities were found within their approaches to cold and long-term missing persons, as well as the identification of some important learning opportunities that may facilitate an improved system for managing and investigating such cases.It is recognised that the task for these cases in Canadian agencies falls with a number of potential personnel and units, including general duties investigators, Missing Persons Coordinators, and a Missing Persons Unit.With no clear place or persons tasked with the responsibility of cold/longterm cases, little active investigation efforts occurred, and there was a complete lack of response structure or system.In contrast, participants in England and Wales are attached to dedicated Cold Case Units (CCUs).Despite this dedicated unit, this only functions on an ad-hoc basis with the reviews of these files.Thus, the remit of their day-to-day responsibilities varies, which impacts their approaches.This in itself may be a limitation, and a more direct comparison of participants may have been beneficial, yet there is still the opportunity to draw parallels and comparisons.
One of the first similarities recognised across both areas was a lack of agreed definitions for cases that become cold/long-term inquiries.This is unsurprising as it is an issue also identified within the field of cold case homicides (c.f.Allsop, 2013;Walton, 2006).That is, after initial investigation classifications, police files, regardless of the type of incident (i.e., criminal-versus non-criminalrelated), tend to face conceptual issues.Ambiguity surrounding terminology can complicate an understanding of these cases for both the investigators tasked with these investigations, but also the victim's family.For example, for investigators, definitional confusion can surface in that it becomes unclear as to who should assume responsibility for the cases and how they should be appropriately managed.For the families of missing persons, both countries acknowledge that liaising with loved ones is imperative when cases become "cold" or "long-term," but the specificities of what is included in such an inquiry are not clearly articulated.This is not attributable to the investigators, as they are often unclear as to their remit and purpose in these cases.Therefore, initiating police responses with clear and appropriate case classification can allow for greater clarity for police investigation and the families of the missing.
In England and Wales, all participants were adamant that cases would typically only be two years old before they are passed to the CCU, but the reasons for them taking the case are often decided by senior management, so it is not clearly articulated to them.This lack of clear organisation complicates the assigning of responsibility for cases, and as demonstrated with Op.Saltmarsh in England and Wales, the concern is that some cases may fall through the gaps.In Canada, reassigning cases once it becomes "cold" or "long-term" may take time, and in that time, whether or not the file will continue to be worked on until it is determined nothing further can be done depended on a range of factors like the officer's dedication to the file, resourcing, competing duties, and agency priority.A similar approach is taken in England and Wales, with the further addition, and perhaps complication, of the informal trajectories that cases are subjected to.For England and Wales, the trajectories, in some ways, are influenced by the "profile" of a case, which has been found to impact other aspects of the work of these files in both areas.
When investigators are tasked with cold/long-term missing persons deemed a significant public interest, English and Welsh participants acknowledge that these cases are more visible and so there is more accountability for managing the case, as well as there being more attention devoted to them over a more extended period.This is beneficial for such cases because investigators can use "active" investigation techniques to obtain information from the public and reinvigorate attention and interest in the case.This similarly occurred in the Canadian context, stressing that once a case turns cold or long-term, media appeals are one of the only "active" investigation tools that police can use to bring about leads.As highlighted in the Canadian analysis, the media interest can also be initiated by the families of the missing, and Ashley Wellman's (2018) work in the US on cold case homicides explores this relationship.Given the status of these files, the needs and police-family relationships experienced by families of cold case homicides are thought to mirror experiences of the families of cold/long-term missing persons.Across countries, a consequence of this for the police, however, is the amount of material generated for each case, all of which must be organised, reviewed, and uploaded/added to their computerised databases.
Both countries emphasised that when new information is provided in a case, it should be reviewed and considered alongside the previous investigative material obtained.While reassuring that these cases can be reviewed as the circumstances dictate, the issue remains: who will take on this responsibility?In Canada, this required agencies to have dedicated civilian support staff (i.e., Historical Case Detective), of which most did not.The two trajectories identified in England and Wales may be beneficial for addressing this gap.Although not all cases will be considered high-risk and may not warrant re-classification to a "no-body murder," assigning cases to dedicated CCUs clarifies who becomes responsible for reviewing any new information.The procedural guidance for England and Wales also suggests that Senior Investigating Officers (SIO) with experience in longterm and complex cases should take charge of their reviews, notably at 28-days.The investigators assigned to CCUs in this study were highly experienced homicide detectives, and most had the experience of leading complex inquiries.Thus, their skill set is advantageous for the management and continued reviews of cold/long-term missing person cases.
A further benefit of CCUs taking responsibility for cold/long-term missing persons is that they would not be required to prioritise the "active" ongoing cases that come into the forces on a regular basis.This was highlighted as a challenge across both countries, so removing the responsibility of these files from the teams/investigators may reduce their demands and prevent the active inquiries from becoming long-term.As this has not been explored in this study or other available literature, this would be an essential consideration for future research.Not only would it reduce the pressures on investigators but provide reassurance for the families that a dedicated system exists for both "active" and cold/long-term missing persons, which prioritises both.However, it is acknowledged that not all dedicated CCUs have the capacity to review these files, given the high prevalence of cold cases and the small numbers of personnel assigned to the teams.

Learning opportunities
There are learning opportunities within the analysis that may benefit the respective countries to improve police responses to cold/long-term missing person cases.Firstly, while the specific investigative approaches for each country were only touched upon, the sharing of best practices across England and Wales is strongly encouraged, and this could be implemented nationally.Although differences in policing organisations, demands, and circumstances of cases can lead to challenges implementing specific management and investigative techniques, successes and challenges can still be shared to improve responses.Thus, learning should not be isolated to individual forces -as is often the case with Force A -and a more open and collaborative approach may benefit forces and individual cases.
Secondly, systemic issues within the wider structure of the police system are apparent across the two countries.A lack of available resources and personnel to devote to cold/long-term missing persons is experienced in both regions, likely impacting the ability to resolve missing person cases traversing into cold/long-term inquiries.Although the CCUs in England and Wales may assume some responsibility for these files, it still exists as an ad-hoc system as it does so in Canada.This approach should be eradicated, and dedicated personnel or teams should be constructed and integrated across the policing system to allow specific resources and attention to such cases.Furthermore, an SIO was identified as the most suitable individual to conduct reviews (ACPO, 2010), but the policy in one force was that responsibility should lie with the Detective Chief Inspector (up to 12 months) and the Detective Superintendent (12 months or older).In England and Wales, the process after 12 months is unclear.In contrast, in Canada, it is wholly unclear when a case initially traverses into "cold" or "long-term," so dedicated individuals and personnel for these investigations should be integrated into the police hierarchy for a clear process of accountability and oversight.
Finally, a procedural guide exists in England and Wales for missing persons.This guide does have its shortcomings for the management and investigation of cold/long-term missing person cases, with more detail, advice, and considerations to be provided.However, this documentation does support investigators in ensuring that all investigative opportunities are fully exploited, with the intent of preventing cases becoming "cold" or "long-term."Given the lack of such a guide across Canada due to differences in policing systems and governments, a similar but more detailed tool may be instrumental for tackling systemic issues surrounding these investigations.Some form of a national or regional procedural guide may be beneficial in Canada not only for standards and best practices but also for collaboration and information sharing.As with the Murder Investigation Manual in the UK (ACPO, 2006), investigators can share examples of learning and best practice developed over the years to facilitate the extension of this documentation.It may be possible to adapt and adopt such guidance for a tool focused on supporting families when their loved one's case becomes "cold" or "long-term."The UK National Sheriffs' Association's (2011) has posited that something similar should be introduced for cold case homicide family members.It may be beneficial to "borrow" from the cold case homicide literature for ascertaining an appropriate framework and guidance for both law enforcement and families on how to manage, prioritise and pursue cold/long-term missing person cases in either region.

Future research
This comparative examination has only touched the surface of the issues surrounding these complex inquiries, and so a proposed research agenda is provided to push interest and academic inquiry into this area: 1. Ascertaining the reasons why cases traverse into long-term/cold inquiries, with the intention of determining if systems, policies, or organisational support can be implemented from an earlier stage to prevent this occurring.2. Identifying the needs of the personnel tasked with both "active" and cold/long-term missing person cases, determining whether clearer and firmer trajectories can be identified, and a clear delineation of roles and responsibilities for cases of each type.3. Understanding the mindset of investigators tasked with such cases, highlighting how cold/ long-term missing person cases may impact officer productivity and subsequently impacting on the possible resolution of cases.4. Identifying mechanisms and tools to support both law enforcement and families during the investigations and management of cold/long-term missing person cases, such as procedural guides, national and/or regional frameworks, and the development of dedicated or specialised units or personnel within agencies.

Notes
1.At the time of data collection, the forces were conducting an audit of their unsolved cases and were still collating up-to-date statistics.2. Forces were chosen for participation for two reasons: Firstly, they were to be conducting reviews of both cold case homicides and long-term missing persons.Secondly, they were only to be conducting this work, with no expectation to work on other inquiries (i.e., reviews of live cases, or domestic homicide reviews).3. Police officers included in the final sample represent both rural and metropolitan areas across the three provinces.4.This is a form used in cases where the individual is presumed dead, detailing information about the individual relevant for the potential identification of human remains.This then goes to the coroner when completed.

Table 1 .
Police response components to cold/long-term missing person cases in England and Wales.

Table 2 .
Police response components to cold/long-term missing person cases in Canada.