Violent or major crime Typically, cold cases are
violent and other major
felony crimes, such as
murder and
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.
Solve rate The rate of cold cases being solved is slowly declining; soon less than 30% will be solved per year.
Suspect identification In the search for suspects, some police organizations have created websites featuring cold cases. For example, the
Texas Rangers have established a website in the hopes that it shall elicit new information and investigative leads.
Tunnel vision Sometimes, a viable suspect has been overlooked or simply ignored due to then-flimsy circumstantial evidence, the presence of a likelier suspect (who is later proven to be innocent), or a tendency of investigators to zero in on someone else to the exclusion of other possibilities (which goes back to the likelier suspect angle)—known as "
tunnel vision".
Improvements in forensics With the advent of and improvements to
DNA testing/
DNA profiling 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. However, to combat that issue, the FBI is switching from using the
Integrated Automated Fingerprint Identification System (IAFIS) to using a newer technology called the
Next Generation Identification (NGI). Other improvements in forensics lie in fields such as: •
Digital forensics, one application of which is to
recover hidden or deleted data. •
Ballistics analysis which involves the evaluation of ammunition and firearms to determine which weapon might have been used in a crime. •
Forensic anthropology which analyzes skeletal remains to determine their cause of death or any other relevant information. •
Mobile forensics and
social media which, since their creation, have had increased involvement in any police case, cold or not. •
Forensic psychology which can be used to analyze crime scenes and identify suspect profiles. •
Facial recognition which has been used to identify suspects based on their facial features. •
Artificial intelligence (AI) which is used in all of the above systems to help analyze data and information from crime scenes. ==Famous criminal examples==