Cold Case
A cold case is a crime, or suspected crime, that has not yet been fully resolved and is not the subject of a recent criminal investigation, but for which new information could emerge from new witness testimony, re-examined archives, new or retained material evidence, as well as fresh activities of the suspect. New technical methods developed after the case can be used on the surviving evidence to analyse the causes, often with conclusive results.
Cold cases are among the most di cult that investigators confront. For a variety of reasons— lack of evidence, strained resources, ine ective investigation—a case becomes cold when initial e orts to solve it prove futile. Clearance rates for homicides and other serious crimes are far below what they were 50 years ago.1 Lackluster rates of solution, combined with new tech- nologies, such as deoxyribonucleic acid (DNA) and automated ngerprint matching, have prompted the police to form cold-case units, designed to address cases that stubbornly resist solution.
Typically, cold cases are violent or other major felony crimes, such as murder or rape which—unlike unsolved minor crimes—are generally not subject to a statute of limitations.
Sometimes disappearances can also be considered cold cases if the victim has not been seen or heard from for some time, such as the case of Natalee Holloway or the Beaumont Children.
About 35% of those cases are not cold cases at all. Some cases become instantly cold when a seeming closed (solved) case is re-opened due to the discovery of new evidence pointing away from the original suspect(s). Other cases are cold when the crime is discovered well after the fact—for example, by the discovery of human remains.[1] Some cases become classified cold cases when a case that had been originally ruled an accident or suicide is re-designated as murder when new evidence emerges.
A case is considered unsolved until a suspect has been identified, charged, and tried for the crime. A case that goes to trial and does not result in a conviction can also be kept on the books pending new evidence.
In some cases, a suspect, often called a "person of interest" or "subject" is identified early on but no evidence definitively linking the subject to the crime is found at that time and more often than not the subject is not forthcoming with a confession. This often happens in cases where the subject has an alibi, alibi witnesses, or lack of forensic evidence. Eventually, the alibi is disproved, the witnesses recanted their statements or advances in forensics helped bring the subjects to justice.
With the advent of and improvements to DNA testing and other forensics technology, many cold cases are being re-opened and prosecuted. Police departments are opening cold case units whose job is to re-examine cold case files. DNA evidence helps in such cases but as in the case of fingerprints, it is of no value unless there is evidence on file to compare it to.
There are three types of cold-case investigations. e rst type is the classic cold-case investigation, in which a detective picks up a case le because of a family or media inquiry or during a procedural review of cases that have remained unsolved for a speci- ed length of time. ese are the least common types of cold-case investigations.
The second type is based on availability of forensic tests. Forensic material from old cases once thought not to be amenable to DNA testing might now be testable due to advances in DNA technology. Federal funds are making this type of cold-case investigation increasingly common.
The third type consists of those cases opened because an individual charged with a crime confesses to the outstanding crime as part of a plea deal or because an eyewitness announces a willingness to nger a suspect in return for leniency after the witness is arrested for participat- ing in a crime.
Cold cases are among the most difficult that investigators confront. For a variety of reasons— lack of evidence, strained resources, ine ective investigation—a case becomes cold when initial e orts to solve it prove futile. Clearance rates for homicides and other serious crimes are far below what they were 50 years ago.1 Lackluster rates of solution, combined with new tech- nologies, such as deoxyribonucleic acid (DNA) and automated ngerprint matching, have prompted the police to form cold-case units, designed to address cases that stubbornly resist solution.
Clearing a cold case does not automatically lead to making an arrest. A substantial por- tion of successful investigations in all sites (from one in three to one in two) did not result in an arrest for a variety of reasons, including inability to locate witnesses, uncooperative witnesses, suspect who is deceased or incarcerated, or DNA results that implicated mul- tiple individuals or were otherwise inconclusive.
In sexual-assault cold cases, even when a suspect DNA match has been made, about one- third of cases are not led because of problems with victim cooperation, credibility, or availability of suspects who are deceased or in prison. However, those cases that are pros- ecuted resulted in convictions and lengthy prison terms more than 90 percent of the time.
Cooperation between police and prosecutors can improve both the efficiency and eeffectiveness of cold-case investigations. Typically, prosecutors are not brought into the picture until cold-case investigations have produced results. But, when police consult with prosecutors beginning at case screening, as is the case in Denver, prosecutors can offer advice on whether the case is likely to produce a conviction if cleared and on what kinds of evidence will be most compelling in court.
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