
Criminal investigation is an
applied science that involves the study of facts that are then used to inform criminal trials. A complete criminal investigation can include
searching,
interviews,
interrogation
Interrogation (also called questioning) is interviewing as commonly employed by law enforcement officers, military personnel, intelligence agencies, organized crime syndicates, and terrorist organizations with the goal of eliciting useful i ...
s,
evidence collection and preservation, and various methods of investigation. Modern-day criminal investigations commonly employ many modern scientific techniques known collectively as
forensic science.
Criminal investigation is an ancient science that may have roots as far back as c. 1700 BCE in the writings of the
Code of Hammurabi. In the code, it is suggested that both the accuser and the accused had the right to present evidence they collected. In the
modern era
The term modern period or modern era (sometimes also called modern history or modern times) is the period of history that succeeds the Middle Ages (which ended approximately 1500 AD). This terminology is a historical periodization that is appli ...
, criminal investigations are most often done by government
police forces.
Private investigators are also commonly hired to complete or assist in criminal investigations.
An early recorded professional criminal investigator was the English
constable
A constable is a person holding a particular office, most commonly in criminal law enforcement. The office of constable can vary significantly in different jurisdictions. A constable is commonly the rank of an officer within the police. Other peop ...
. Around 1250 CE, it was recorded that the constable was to "...record...matters of fact, not matters of judgment and law."
Investigative techniques
In seeking "indicators of suspicion" in investigations, suspects will need to have had:
*
Motive to commit the crime (for example, financial gain or to seek revenge)
* Means to commit the crime (including tools and physical capabilities)
* Opportunity to commit the crime (including being at the crime scene at the time of the offence)
They will also establish the relationships between the victim and any potential offenders.
Investigation priority bias problems and proposed solutions

After observing recent changes in the demographic composition of particular crimes during higher priority of their investigation, such as the increase of the percentage of women convicted for joining and fighting for
terrorist organizations from a very low percentage (similar to those of murder and rape) to almost as many women as men (women in the 40–50 percent range in some jurisdictions) as the priority of investigating terror crimes increased, certain criminologists are expressing the notion that there may be more crimes that would change their demographics if they got higher priority. These criminologists theorize that in the case of limited budgets, criminal investigators rely on profiled and statistical likelihood of particular groups of people being convicted for the type of crimes that are being investigated, and ignore complaints that are filed about people who they consider less likely to commit the crimes or give the tracking or individual matching to the evidence lower priority. According to the hypotheses, even a minimal or nonexistent difference in the likelihood of committing crimes can be hidden behind a difference of a factor by many multiples in the likelihood of being convicted due to
self-fulfilling prophecies in the statistics. These criminologists feel that criminals who are not getting caught, due to being profiled as unlikely offenders, are a major problem. Some of these criminologists propose an increased number of police officers. Others argue that investigations of the evidence are more expensive than police patrols and that not all crimes can be investigated, suggesting that profiling of
criminal psychology should be replaced with randomized priorities of individual suspects within similar types of crime. The latter criminologists also argue that such randomization would not only fight hidden crimes by exposing the currently unsuspected criminals to the risk of being punished, but also that the abolition of profiling by
forensic psychology
Forensic psychology is the development and application of scientific knowledge and methods to help answer legal questions arising in criminal, civil, contractual, or other judicial proceedings. Forensic psychology includes both research on various ...
and forensic psychiatry would be a monetary saving that could be used for investigation of technical evidence, tracking of criminals who are hiding, and other investigation work that can reduce the need to ignore complaints for budget reasons.
["Incapacitation: Trends and New Perspectives" 2016 by Marius Duker, Marijke Malsch]
See also
*
Murder book
References
External links
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{{Authority control
18th-century BC establishments
Applied sciences
Forensic disciplines