A detective is an investigator, usually a member of a
law enforcement agency
A law enforcement agency (LEA) is any government agency responsible for the enforcement of the laws.
Jurisdiction
LEAs which have their ability to apply their powers restricted in some way are said to operate within a jurisdiction.
LEAs ...
. They often collect information to solve
crimes
In ordinary language, a crime is an unlawful act punishable by a state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definitions of", in Can ...
by talking to witnesses and informants, collecting physical evidence, or searching records in databases. This leads them to arrest criminals and enable them to be convicted in court.
A detective may work for the police or
privately.
Overview
Informally, and primarily in
fiction
Fiction is any creative work, chiefly any narrative work, portraying individuals, events, or places that are imaginary, or in ways that are imaginary. Fictional portrayals are thus inconsistent with history, fact, or plausibility. In a traditi ...
, a detective is a licensed or unlicensed person who solves
crime
In ordinary language, a crime is an unlawful act punishable by a State (polity), state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definit ...
s, including historical crimes, by examining and evaluating clues and personal records in order to uncover the identity and/or whereabouts of criminals.
In some
police departments
The police are a constituted body of persons empowered by a state, with the aim to enforce the law, to ensure the safety, health and possessions of citizens, and to prevent crime and civil disorder. Their lawful powers include arrest and t ...
, a detective position is achieved by passing a written test after a person completes the requirements for being a
police officer
A police officer (also called a policeman and, less commonly, a policewoman) is a warranted law employee of a police force. In most countries, "police officer" is a generic term not specifying a particular rank. In some, the use of the ...
. In many other police systems, detectives are
college graduates who join directly from
civilian
Civilians under international humanitarian law are "persons who are not members of the armed forces" and they are not "combatants if they carry arms openly and respect the laws and customs of war". It is slightly different from a non-combatant, b ...
life without first serving as uniformed officers. Some argue that detectives do a completely different job and therefore require completely different training, qualifications, qualities and abilities than uniformed officers. The opposing argument is that without previous service as a uniformed patrol officer, a detective cannot have a great enough command of standard police procedures and problems and will find it difficult to work with uniformed colleagues.
Some are not public officials, and may be known as a
private investigator
A private investigator (often abbreviated to PI and informally called a private eye), a private detective, or inquiry agent is a person who can be hired by individuals or groups to undertake investigatory law services. Private investigators of ...
, colloquially referred to, especially in fiction, as a "PI" or "private eye", "private dick" or "shamus".
Organization
The detective branch in most large police agencies is organized into several squads and departments, each of which specializes in
investigation into a particular type of crime or a particular type of undercover operation, which may include:
homicide
Homicide occurs when a person kills another person. A homicide requires only a volitional act or omission that causes the death of another, and thus a homicide may result from accidental, reckless, or negligent acts even if there is no inten ...
,
robbery
Robbery is the crime of taking or attempting to take anything of value by force, threat of force, or by use of fear. According to common law, robbery is defined as taking the property of another, with the intent to permanently deprive the perso ...
, spot
burglary
Burglary, also called breaking and entering and sometimes housebreaking, is the act of entering a building or other areas without permission, with the intention of committing a criminal offence. Usually that offence is theft, robbery or murder ...
,
auto theft
Motor vehicle theft (also known as a car theft and, in the United States, grand theft auto) is the criminal act of stealing or attempting to steal a motor vehicle. Nationwide in the United States in 2020, there were 810,400 vehicles reporte ...
,
organized crime
Organized crime (or organised crime) is a category of transnational, national, or local groupings of highly centralized enterprises run by criminals to engage in illegal activity, most commonly for profit. While organized crime is generally th ...
s,
missing person
A missing person is a person who has disappeared and whose status as alive or dead cannot be confirmed as their location and condition are unknown.
A person may go missing through a voluntary disappearance, or else due to an accident, crime, de ...
s,
juvenile crime
Juvenile delinquency, also known as juvenile offending, is the act of participating in unlawful behavior as a minor or individual younger than the statutory age of majority. In the United States of America, a juvenile delinquent is a person ...
,
fraud
In law, fraud is intentional deception to secure unfair or unlawful gain, or to deprive a victim of a legal right. Fraud can violate civil law (e.g., a fraud victim may sue the fraud perpetrator to avoid the fraud or recover monetary compens ...
,
narcotic
The term narcotic (, from ancient Greek ναρκῶ ''narkō'', "to make numb") originally referred medically to any psychoactive compound with numbing or paralyzing properties. In the United States, it has since become associated with opiates ...
s,
vice
A vice is a practice, behaviour, or habit generally considered immoral, sinful, criminal, rude, taboo, depraved, degrading, deviant or perverted in the associated society. In more minor usage, vice can refer to a fault, a negative character tra ...
,
criminal intelligence
Criminal intelligence is information compiled, analyzed, and/or disseminated in an effort to anticipate, prevent, or monitor criminal activity.
The United States Army Military Police Corps defines criminal intelligence as information gathered or c ...
,
aggravated assault
An assault is the act of committing physical harm or unwanted physical contact upon a person or, in some specific legal definitions, a threat or attempt to commit such an action. It is both a crime and a tort and, therefore, may result in crim ...
/
battery
Battery most often refers to:
* Electric battery, a device that provides electrical power
* Battery (crime), a crime involving unlawful physical contact
Battery may also refer to:
Energy source
*Automotive battery, a device to provide power t ...
,
sexual assault
Sexual assault is an act in which one intentionally sexually touches another person without that person's consent, or coerces or physically forces a person to engage in a sexual act against their will. It is a form of sexual violence, which ...
,
computer crime
A cybercrime is a crime that involves a computer or a computer network.Moore, R. (2005) "Cyber crime: Investigating High-Technology Computer Crime," Cleveland, Mississippi: Anderson Publishing. The computer may have been used in committing th ...
,
domestic violence
Domestic violence (also known as domestic abuse or family violence) is violence or other abuse that occurs in a domestic setting, such as in a marriage or cohabitation. ''Domestic violence'' is often used as a synonym for ''intimate partner ...
,
surveillance
Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing or directing. This can include observation from a distance by means of electronic equipment, such as c ...
, and
arson
Arson is the crime of willfully and deliberately setting fire to or charring property. Although the act of arson typically involves buildings, the term can also refer to the intentional burning of other things, such as motor vehicles, wat ...
, among others.
In police departments of the United States, a regular detective typically holds the rank of "Detective". The rank structure of the officers who supervise them (who may or may not be detectives themselves) varies considerably by department. In Commonwealth police forces, detectives have equivalent ranks to uniformed officers but with the word "Detective" prepended to it (e.g. "Detective Constable").
Private detectives
In some countries, courts and judicial processes have yet to recognize the practice of private detectives. In Portugal, presented proof loses significance when private detectives collect it. Even under this circumstance, the practice is in demand and ruled by a code of conduct.
Citizen detectives
A citizen detective, also known as an amateur detective, is an individual who devotes his or her time and expertise to aid in the
solving of crime, without compensation or expectation of reward. Citizen detectives are
private citizen
A private citizen is someone who does not have an official or professional role in a given situation.
The same person may be a private citizen in one role, and an official in another. For example, a legislator is an official when voting in the l ...
s that have no real professional relationship with law enforcement and lack any
rational-legal authority
Rational-legal authority (also known as rational authority, legal authority, rational domination, legal domination, or bureaucratic authority) is a form of leadership in which the authority of an organization or a ruling regime is largely tied to ...
whatsoever. The reasons why a private citizen might try to solve a crime vary from trying to ensure justice for a friend or relative, a strong dislike for crime and support for
law and order
In modern politics, law and order is the approach focusing on harsher enforcement and penalties as ways to reduce crime. Penalties for perpetrators of disorder may include longer terms of imprisonment, mandatory sentencing, three-strikes laws a ...
, or just recreational enjoyment.
As with other kinds of detectives, citizen detectives try to solve crimes in multiple ways such as
searching a crime scene,
interviewing
An interview is a structured conversation where one participant asks questions, and the other provides answers.Merriam Webster DictionaryInterview Dictionary definition, Retrieved February 16, 2016 In common parlance, the word "interview" ...
and/or
interrogating
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 informa ...
suspects and witnesses, doing
surveillance
Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing or directing. This can include observation from a distance by means of electronic equipment, such as c ...
on
persons of interest
"Person of interest" is a term used by law enforcement in the United States, Canada, and other countries when identifying someone possibly involved in a criminal investigation who has not been arrested or formally accused of a crime. It has no le ...
, collecting
evidence
Evidence for a proposition is what supports this proposition. It is usually understood as an indication that the supported proposition is true. What role evidence plays and how it is conceived varies from field to field.
In epistemology, evidenc ...
, acting as
sources
Source may refer to:
Research
* Historical document
* Historical source
* Source (intelligence) or sub source, typically a confidential provider of non open-source intelligence
* Source (journalism), a person, publication, publishing institute o ...
for
local news, giving anonymous tips to the police and at times even making
citizens’ arrests while a crime is being committed. Citizen detectives can also help law enforcement by becoming
witnesses
In law, a witness is someone who has knowledge about a matter, whether they have sensed it or are testifying on another witnesses' behalf. In law a witness is someone who, either voluntarily or under compulsion, provides testimonial evidence, e ...
for
prosecutors
A prosecutor is a legal representative of the prosecution in states with either the common law adversarial system or the Civil law (legal system), civil law inquisitorial system. The prosecution is the legal party responsible for presenting the ...
, participating in local
neighborhood watch
A neighborhood watch or neighbourhood watch (see spelling differences), also called a crime watch or neighbourhood crime watch, is an organized group of civilians devoted to crime and vandalism prevention within a neighborhood.
The aim of neig ...
groups, acting as
citizen observers for law enforcement, or even aiding the police in searching for and arresting suspects as a
posse
Posse is a shortened form of posse comitatus, a group of people summoned to assist law enforcement. The term is also used colloquially to mean a group of friends or associates.
Posse may also refer to:
Arts and entertainment
* ''Posse'' (1975 ...
. However, there have been cases of citizen detectives unintentionally compromising investigations if they lack real crime solving skills or even committing acts against suspected criminals that could be deemed
vigilantism
Vigilantism () is the act of preventing, investigating and punishing perceived offenses and crimes without Right, legal authority.
A vigilante (from Spanish, Italian and Portuguese “vigilante”, which means "sentinel" or "watcher") is a pers ...
in nature.
History
Before the 19th century, there were few municipal
police
The police are a constituted body of persons empowered by a state, with the aim to enforce the law, to ensure the safety, health and possessions of citizens, and to prevent crime and civil disorder. Their lawful powers include arrest and t ...
departments, though the first had been created in Paris in 1667. As police activities moved from appointees helped by volunteers to professionals, the idea of dedicated detectives did not immediately arise. The first
private detective agency was founded in Paris in 1833 by
Eugène François Vidocq
Eugène-François Vidocq (; 24 July 1775 – 11 May 1857) was a French criminal turned criminalist, whose life story inspired several writers, including Victor Hugo, Edgar Allan Poe and Honoré de Balzac. The former criminal became the founder a ...
, who had also headed a police agency in addition to being a criminal himself. Police detective activities were pioneered in England by the
Bow Street Runners
The Bow Street Runners were the law enforcement officers of the Bow Street Magistrates' Court in the City of Westminster. They have been called London's first professional police force. The force originally numbered six men and was founded in 1 ...
and later the
Metropolitan Police Service
The Metropolitan Police Service (MPS), formerly and still commonly known as the Metropolitan Police (and informally as the Met Police, the Met, Scotland Yard, or the Yard), is the territorial police force responsible for law enforcement and ...
in Greater London. The first police detective unit in the United States was formed in 1846 in Boston.
Techniques
Street work
Detectives have a wide variety of techniques available in conducting investigations. However, the majority of cases are solved by the interrogation of suspects and the interviewing of witnesses, which takes time. Besides interrogations, detectives may rely on a network of informants they have cultivated over the years. Informants often have connections with persons a detective would not be able to approach formally. Evidence collection and preservation can also help in identifying a potential suspect(s).
Criminal investigation
The investigation of criminal activity is conducted by the police. Criminal activity can relate to road use such as speeding, drunk driving, or to matters such as theft, drug distribution, assault, fraud, etc. When the police have concluded their investigation, a decision on whether to charge somebody with a criminal offense will often be made by prosecuting counsel having considered the evidence produced by the police.
In criminal investigations, once a detective has suspects in mind, the next step is to produce evidence that will stand up in a court of law. The best way is to obtain a confession from the suspect; usually, this is done by developing rapport and at times by seeking information in exchange for potential perks available through the attorney's office, such as entering for a lesser sentence in exchange for usable information. In some countries, detectives may lie, mislead and psychologically pressure a suspect into an admission or confession as long as they do this within procedural boundaries and without the threat of violence or promises outside their control. This is not permitted in
England and Wales
England and Wales () is one of the three legal jurisdictions of the United Kingdom. It covers the constituent countries England and Wales and was formed by the Laws in Wales Acts 1535 and 1542. The substantive law of the jurisdiction is Eng ...
, where the interview of suspects and witnesses is governed by the
Police and Criminal Evidence Act 1984
The Police and Criminal Evidence Act 1984 (PACE) (1984 c. 60) is an Act of Parliament which instituted a legislative framework for the powers of police officers in England and Wales to combat crime, and provided codes of practice for the exercise ...
.
Forensic evidence
Physical
forensic evidence
Forensic identification is the application of forensic science, or "forensics", and technology to identify specific objects from the trace evidence they leave, often at a crime scene or the scene of an accident. Forensic means "for the courts".
H ...
in an investigation may provide leads to closing a case.
Forensic science
Forensic science, also known as criminalistics, is the application of science to criminal and civil laws, mainly—on the criminal side—during criminal investigation, as governed by the legal standards of admissible evidence and criminal ...
(often shortened to forensics) is the application of a broad spectrum of sciences to answer questions of interest to the legal system. This may be in relation to a crime or to a civil action. Many major police stations in a city, county, or state, maintain their own forensic laboratories while others contract out the services.
Records investigation
Detectives may use public and private records to provide background information on a subject. Police detectives can search through files of fingerprint records.
Police
The police are a constituted body of persons empowered by a state, with the aim to enforce the law, to ensure the safety, health and possessions of citizens, and to prevent crime and civil disorder. Their lawful powers include arrest and t ...
maintain records of people who have committed
felonies
A felony is traditionally considered a crime of high seriousness, whereas a misdemeanor is regarded as less serious. The term "felony" originated from English common law (from the French medieval word "félonie") to describe an offense that resu ...
and some
misdemeanor
A misdemeanor (American English, spelled misdemeanour elsewhere) is any "lesser" criminal act in some common law legal systems. Misdemeanors are generally punished less severely than more serious felonies, but theoretically more so than adm ...
s. Detectives may search through records of criminal arrests and convictions, photographs or ''mug shots'', of persons arrested, ands, hotel registration information, credit reports,
answering machine
An answering machine, answerphone or message machine, also known as telephone messaging machine (or TAM) in the UK and some Commonwealth countries, ansaphone or ansafone (from a trade name), or telephone answering device (TAD), was used for a ...
messages, phone conversations, surveillance camera footage, and technology used for communication.
Across the world
United Kingdom
Before 2017, prospective
British
British may refer to:
Peoples, culture, and language
* British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies.
** Britishness, the British identity and common culture
* British English, ...
police detectives must have completed at least two years as a uniformed officer before applying to join the
Criminal Investigation Department
The Criminal Investigation Department (CID) is the branch of a police force to which most plainclothes detectives belong in the United Kingdom and many Commonwealth nations. A force's CID is distinct from its Special Branch (though officers of b ...
. Since 2017, applicants from outside the police force may join directly as trainee detectives.
UK Police
Law enforcement in the United Kingdom is organised separately in each of the legal systems of the United Kingdom: England and Wales, Northern Ireland and Scotland. Most law enforcement is carried out by police officers serving in regional po ...
must also pass the National Investigators' Examination in order to progress to subsequent stages of the Initial Crime Investigators Development Programme in order to qualify as a detective.
United States
Before becoming a police detective, one must attend a law enforcement academy, providing the officer with a foundation of education with 16 to 24
college units. After graduation from the law enforcement academy, the officer undergoes job training with a field training officer for a period specified by the law enforcement agency and continues to work while on a probationary period, ranging from one to two years.
During the probationary period, the officer is assigned to look for evidence. During this time, the officer is supervised and mentored by a sergeant with years of experience. Some officers further their college education by attending a two- or four-year college or university, attaining a degree in criminal justice or administration of criminal justice. Colleges have options for a concentration or certificate in a specialized field of criminal investigation.
Through years of on-the-job training or college education, officers may participate in a competitive examination, testing their knowledge, skills and abilities regarding criminal investigation, criminal procedure, interview and interrogation, search and seizure, collection and preservation of evidence, investigative report writing, criminal law, court procedure and providing testimony in court. Competitive examinations are conducted by selected senior law enforcement officials. Following testing, a list of results is provided by the department. At the department's discretion, some or all of the officers on the list are promoted to the rank of detective. Some departments have classes of detectives which increase the detective's rank after successful experience.
Private investigators are licensed by the state in which they work (some states do not require licensing, but most do). In addition to the state examination, applicants testing for a private investigation license must also meet stringent requirements, which include college education, a range of two to four years of full-time investigation experience and the successful adjudication of a criminal and civil background check conducted by state investigators. Private investigators are licensed to conduct civil and criminal investigations in the state in which they are licensed, and are protected by statutes of that state. In states requiring licensure, statutes make it unlawful for any person to conduct a criminal investigation without a license, unless exempted by the statute (i.e., law enforcement officers or agents, attorneys,
paralegals
A paralegal, also known as a legal assistant, or paralegal specialist is a professional who performs tasks that require knowledge of legal concepts but not the full expertise of a lawyer with a license to practice law. The market for paralegals ...
,
claims adjuster
A claims adjuster, desk adjuster, field adjuster, or general adjuster (claim adjuster, claims handler, claim handler or loss adjuster in the United Kingdom, Ireland, Australia, South Africa, the Caribbean and New Zealand) investigates insurance cla ...
s).
See also
*
Hotel detective
A hotel detective is a person in plain clothes hired to monitor the security of a hotel and investigate various security, morality, or rule violations therein. They are distinct from uniformed security guards employed by a hotel.
Hotel detecti ...
*
Inspector
Inspector, also police inspector or inspector of police, is a police rank. The rank or position varies in seniority depending on the organization that uses it.
Australia
In Australian police forces, the rank of inspector is generally the ne ...
*
Investigator (disambiguation)
Investigator may refer to:
Occupations Government and law
* Detective, a person who investigates crimes, can be a rank and job in a police department, state or federal employee, or a civilian called a private detective
* Inspector, a police rank ...
*
Law enforcement agency
A law enforcement agency (LEA) is any government agency responsible for the enforcement of the laws.
Jurisdiction
LEAs which have their ability to apply their powers restricted in some way are said to operate within a jurisdiction.
LEAs ...
*
Police rank
Police ranks are a system of hierarchical relationships in police organizations. The rank system defines authority and responsibility in a police organization, and affects the culture within the police force. Police ranks, dependent on country, ar ...
*
Private investigator
A private investigator (often abbreviated to PI and informally called a private eye), a private detective, or inquiry agent is a person who can be hired by individuals or groups to undertake investigatory law services. Private investigators of ...
*
Police
The police are a constituted body of persons empowered by a state, with the aim to enforce the law, to ensure the safety, health and possessions of citizens, and to prevent crime and civil disorder. Their lawful powers include arrest and t ...
*
Police officer
A police officer (also called a policeman and, less commonly, a policewoman) is a warranted law employee of a police force. In most countries, "police officer" is a generic term not specifying a particular rank. In some, the use of the ...
*
Undercover operation
To go "undercover" (that is, to go on an undercover operation) is to avoid detection by the object of one's observation, and especially to disguise one's own identity (or use an assumed identity) for the purposes of gaining the trust of an indi ...
*
Spy agent
*
Special agent
*
Detective fiction
Detective fiction is a subgenre of crime fiction and mystery fiction in which an investigator or a detective—whether professional, amateur or retired—investigates a crime, often murder. The detective genre began around the same time as s ...
*
VALCRI
Visual Analytics for Sense-making in Criminal Intelligence Analysis (VALCRI) is a software tool that helps investigators to find related or relevant information in several criminal databases. The software uses big data processes to aggregate info ...
References
{{Authority control
Criminal investigation
Police ranks
Law enforcement