The goal of law enforcement is to promote public safety and welfare. A law enforcement officer (also called peace officer) is any public-sector employee or agent whose duties involve enforcing laws, collecting evidence, and catching criminals. They may be employed by local, special, State or Federal agencies.
Law enforcement officers include police officers, prison officers, customs officers, immigration officers, constables, bailiffs, probation officers, parole officers, arson investigators, auxiliary officers, state troopers, sheriffs, marshals, and their deputies – basically anyone “sworn, badged, and armable” who can make an arrest, or refer such arrest for a criminal prosecution.
In the majority of states in the U.S., actively-employed state-certified peace officers, regardless of the capacity in which they are employed (private, public, company, security, campus, etc.), have the ability to pursue and apprehend someone suspected of committing a felony outside of their normal jurisdiction.
In the United States, sheriffs and police officers perform very different functions, although both are considered law enforcement and the two organizations may cooperate. The word “sheriff” derives from the Old English concept of a “shire reeve,” a man who looked out for the interests of the King in a shire, or district, of England. Since at least the 1600s in America, the term “sheriff” has been used to refer to a law enforcement officer.
The word “police” comes from the ancient Greek term “polissoos,” which referred to a person who was guarding a city. In the late 1600s and early 1700s, men who patrolled a “beat” enforcing local laws began to emerge, and they became known as policemen. One of the first truly organized police forces was the Metropolitan Police in London.
In contrast to a Sheriff, who in most states is elected by the voters of a county, a Chief of Police is usually a municipal employee who owes his or her allegiance to a city or town. But perhaps the most significant division in law enforcement is between police and detectives. Most police officers wear uniforms. However, detectives often work in regular clothes. Many detectives are part of regular police forces, but they usually have separate duties from police officers.
Specialized preventive and detective personnel exist within many law enforcement organizations either for dealing with particular types of crime, such as traffic law enforcement and crash investigation, homicide, or fraud; or for situations requiring specialized skills, such as underwater search, aviation, explosive device disposal (“bomb squad”), and computer crime.
Many larger jurisdictions also employ specially selected and trained quasi-military units armed with military-grade weapons for the purposes of dealing with particularly violent situations beyond the capability of a patrol officer response, including high-risk warrant service, hostage situations, barricaded suspects, and riots. In the United States these units are commonly known as SWAT (Special Weapons And Tactics) teams.
Although they wear different uniforms, the hiring requirements of all law enforcement officers – which require admission to and completion of academy training – are generally similar. For example, in addition to being a high school graduate, an applicant must have: stamina to sit, stand, or walk for long periods of time; strength to subdue persons; dexterity to fire a handgun; tolerance to work under adverse conditions; and the knowledge, skills, and abilities necessary to do the work. Law enforcement candidates often have military experience, college training in police science, or a bachelor’s degree in law enforcement or another related field such as Criminal Justice or Sociology.
Candidates must take a written exam, submit to a physical exam, and undergo a background check. They may also be required to take a psychological exam and polygraph exam. If the candidate passes all of these tests, he or she is interviewed; and if the interview goes well, the candidate is sent to a training academy. At the academy, the cadet will participate in an academic program which is designed to prepare them for active duty. The trainee will learn how to handle firearms, drive a law enforcement vehicle, and perform other necessary tasks. After graduation, the candidate is accepted into the department where he or she interviewed. An applicant may also attend an academy and then apply into a department, although this tends to be more rare.
Government Special Agent hiring (ATF, DEA, FBI, etc.) is fiercely competitive, with typically less than 5% of qualified applicants being selected. They must possess at minimum a four year bachelor degree and competitive work experience (which is usually four or more years at a local or state police department). Applicants must pass a rigorous background check in order to achieve, at minimum, a top secret clearance.
Law enforcement work is challenging and offers people an opportunity to serve their communities. Law enforcement officers usually work on foot or ride in cars, but a few ride horses, bikes, or motorcycles. Some work in boats on rivers and in harbors. Some law enforcement officers work with dogs. Law enforcement officers must be healthy, strong, and of good character. They take big risks when chasing criminals or when they go to make an arrest. Good training, teamwork, and equipment help keep law enforcement officers safe.
Auxiliary Officer – A part-time reserve of a regular police force who may be an unpaid volunteer or paid member of the police service with which they are affiliated. Auxiliary officers are often called upon to assist in such things as large scale searches for missing persons, and to provide traffic control or crowd control at major events.
Bailiff – An official in a court of law who looks after jurors and prisoners while keeping order and maintaining security.
Bodyguard – A type of security operative who protects a public, wealthy, or politically important figure from danger. Some high-profile celebrities and CEOs also use bodyguards. Bodyguards often have military, police or security backgrounds as well as training in firearms tactics, unarmed combat, tactical driving, and first aid.
Bounty Hunter – A bounty hunter pursues fugitives for a monetary reward (bounty). Most bounty hunters are employed by bail bondsmen. If a defendant fails to appear in court, the bond agent is allowed by law and/or contractual arrangement to hire a bounty hunter to bring the defendant to the court and recover the money paid out under the bond.
Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) Agent – Charged with the investigation and prevention of federal offenses involving the unlawful use, manufacture, and possession of firearms and explosives, and illegal trafficking of alcohol and tobacco products.
Bureau of Diplomatic Security Special Agent – Charged with the protection of dignitaries and diplomatic missions.
Constable/Deputy Constable – Depending on the state, may be a fully empowered law enforcement officer or merely an official responsible for serving summonses and subpoenas for people to appear in court.
Customs and Border Protection Officer – The CBP has more sworn, armed law enforcement officers than any other agency in the U.S., to enforce U.S. trade, customs, and immigration regulations.
Drug Enforcement Administration (DEA) agent – The federal law enforcement agency tasked with combating drug smuggling and use within the U.S.
Federal Air Marshal – Aviation law enforcement and security.
Federal Bureau of Investigation (FBI) Agent – Investigates federal crimes and internal intelligence.
Federal Flight Deck Officer – An eligible flight crew member deputized as a Federal Law Enforcement Officer.
Fire Marshal/Deputy Fire Marshal – An experienced firefighter who is a sworn law enforcement officer charged with enforcing fire codes and investigating the cause of fires and explosions.
Firefighter – Every fire scene is technically a crime scene until deemed otherwise, so there is often overlap between the responsibilities of responding firefighters and police officers such as evidence and scene protection, and specific powers of enforcement and control in fire and emergency situations. As in a typical law enforcement investigation, there will be a fire scene investigator or arson investigator.
Fish and Game Warden – Enforces laws pertaining to the hunting, fishing, and trapping of wild animals.
Jailer/Prison Guard/Corrections Officer/Detention Officer – Responsible for the supervision, safety and security of prisoners in a prison, jail, or other secure custody.
Military Policeman – Each branch of the military maintains its own police force to enforce laws and regulations on their military installations. Military police provide area security, and are also trained in dealing with prisoners of war and other detainees.
Parole Officer – Supervises offenders conditionally released from incarceration.
Park Ranger/Forest Ranger – Law enforcement officers charged with protecting and preserving national parks, forests, and other federally managed areas by enforcing laws and regulations, performing searches and rescues, and helping to direct forest- and fire-control efforts.
Police Officer – Police officers are generally charged with the prevention and detection of crime, the apprehension of criminals, and the maintenance of public order within the boundaries of a city or town. Police functions include protecting life and property, enforcing criminal law, crime scene investigations, giving out tickets, directing traffic, and crowd control. They sometimes testify in court. The police also perform other public services such as safety education.
Private Detective/Private Investigator – A person hired by an individual or group to undertake investigatory law services. PIs are often former police officers, law enforcement agents, spies, military, bodyguards or security guards. While PIs may investigate criminal matters, most do not have police powers, and as such they have only the powers of citizen’s arrest and detainment that any other citizen has.
Private Police/Security Guard – Private security firms in the U.S. employ more security guards, patrol personnel, and detectives than the federal, state and local governments combined, fulfilling many of the beat-patrol functions of public police. Specific types of private police include casino and mall security, and the specialized railroad police. But security guards are not normally law enforcement officers and thus do not have the ability to arrest civilians unless they are also peace officers or have been granted powers to enforce particular laws or regulations, and given authority to detain or apprehend.
Probation Officer – Supervises offenders who have not been incarcerated but whose activities are restricted by a judge.
Sheriff/Deputy Sheriff – A sheriff is the law enforcement officer of a county or state, and he or she swears in deputies who have similar powers. Sheriffs generally patrol outside the boundaries of towns and cities, although a town without a police department may request that a sheriff patrol within city limits.
State Trooper/Highway Patrol Officer – A state law enforcement officer working to patrol the highways.
Texas Ranger – The oldest statewide law enforcement agency, the Texas Rangers began in 1835 as a cross between cowboys and police officers. They rode on horseback and protected settlers from Indian attacks and other dangers. Today, the Rangers are an investigative arm of the Texas Department of Public Safety.
Town Marshal/Deputy Town Marshal – Appointed or elected by some communities as the top criminal law enforcement officer, like a Chief of Police.
U.S. Coast Guard officer – Maritime law enforcement.
U.S. Marshal/Deputy Marshal – Since 1789, the nation’s oldest professional civil service unit of federal police has been charged with transporting federal prisoners, apprehending fugitives, and ensuring witness safety.
U.S. Postal Service Police – The Postal Inspection Service has the oldest origin of any federal law enforcement agency in the U.S., tracing its roots back to 1772.
U.S. Secret Service – Federal special agents and uniformed officers protect our nation’s leaders, visiting world leaders, national events, and the integrity of the nation’s currency.