"That's nice work, boys!"
— Chief Clancy Wiggum, The Simpsons
In its original conception, The United States uses a federal system of government. In theory, this means that the States hold general police power, while the national government only has power over crime between different states, crimes affecting interstate commerce, criminals who cross state lines, or crime committed by members of the national armed forces, or crime that crosses the international borders. Hang with us. The theory was the easy part. The hard part is, the theory has been complicated by 2+ centuries of judicial precedents. Simply put, these are legal cases in which the decision by the court establishes a new rule or principle that other courts follow from that time on. There have also been Constitutional Amendments that affect the original concept (notably the 14th Amendment). Finally, the practical application was immensely complicated by what some Americans of Southern heritage still refer to as "The Late Unpleasantness". All of this has granted all American police agencies a huge amount of power, far beyond anything imagined by the folks who drafted the Constitution. And as we will see, there is an astounding array of US police agencies. While there are significant differences amongst them, all have several things in common.
- First, unlike some police forces, the law enforcement agencies in the US issue firearms to their officers. Every sworn member of every agency listed after this has (or is authorized to have) a gun strapped on. Sworn members are those who have taken an oath to uphold the US Constitution, their state's constitution, and the laws of their particular jurisdiction; in addition to carrying firearms openly or concealed, these officers are also those empowered to make arrests.
- The firearms carried vary from jurisdiction to jurisdiction. Until the late 20th century, most officers carried 5 or 6 shot revolvers chambered in .38 caliber or .357 Magnum, and Colt or Smith & Wesson were the manufacturers of choice. This was mostly because, contrary to what you might think, police departments assumed no familiarity with weapons with their new recruits, and the "wheelgun" was much easier to learn than most semi-autos of the day. The long association of revolvers with the police, of course, helped create the Revolvers Are Just Better trope. However, one of the things the Dirty Harry series got right was the rarity of the "most powerful handgun in the world;'' most officers saw the increase in firepower of the .44 Magnum as not being worth the vastly increased hand strength and target practice necessary to handle one well.
- More or less concurrently with the "War on Drugs," departments across the country began switching to semi-automatic handguns with 10, 12 or even 16 round magazines, chambered in 9mm or .40 caliber; Glock, Beretta, Sig Sauer seem to be the most popular brands. Almost all jurisdictions also require 12 gauge shotguns as standard equipment in patrol cars. SWAT teams use even more lethal weaponry, including SniperRifles, so-called "assault weapons" (semi-automatic rifles, usually based on the Armalite AR-15 design), and even submachine guns. And undercover officers may use almost anything that's easily concealable.
- Sworn, uniformed officers also carry one or more of a selection of non-lethal weapons. The old-fashioned nightstick is still around, but many departments have replaced it with the single tonfa. Chemical ('pepper') spray and tasers are also becoming more common. Nevertheless, since these weapons are only designed to be non-lethal, and have in fact killed people who suffered from certain medical conditions, their use is controversial as well. Further, because these weapons — except chemical sprays — are not easily concealable, most plainclothes and all undercover officers only use firearms.
- However, it is not true that every employee of a US police department is armed. Virtually all of the following agencies also have "civilian" or unsworn employees. These include dispatchers (the communications personnel who receive 911 calls and send radio calls to the police), crime scene analysts, and forensic technicians. (Examples of the latter in current fiction include Barry Allen and Edward Nygma, respectively.) These employees are not authorized to make arrests or pack heat.
- Second, the sheer size of the United States (for quick comparison, Texas, the 2nd largest state, is roughly the same size as the nation of France; Rhode Island, the smallest, is almost twice the size of Luxembourg) has made the automobile an equally indispensable part of police life. Police cars in the U.S. may be either marked or unmarked. While marked police cars in most countries run the gamut from minicars to near-exotic sports models, American cops favor big, preferably rear-drive and V8-powered sedans. For many years more than ninety percent have been Ford Crown Victorias (Police Interceptor model)- Everybody Owns a Ford as almost literal Truth in Television. The Crown Victoria was phased out after the 2012 model year, however, and replaced by a new-model Ford Taurus. As the Crown Vics age out of service, other models have risen in popularity.
- Ford itself clams that its Taurus police model and its "Interceptor" brand of the Ford Explorer together sold almost 25,000 units in 2014. Other manufacturers angle for their share of the police market in different ways. The Dodge Charger was already a real competitor to the Crown Vic, due to it being more powerful, maneuverable, comfortable, and notably, not a 30-year-old design. Also, in many northern states, the Chevy Impala had become a common sight, due to the fact that it has front-wheel drive - not as badass as rear-wheel drive, but much more useful for driving in six inches or more of snow. Oh, and it's also more fuel efficient than the heavy Crown Vic and the big-engined Charger.
- Unmarked cars used by uniformed officers (Yes, this is common, often for highway patrol duty) tend to be the same models as the marked ones, which makes spotting them easier than the cops would like. However, undercover officers can and do drive anything, because many of their vehicles are cars impounded from their owners for various offenses.
- Jurisdictions that have K9 units (not that one) have special transportation needs; since a K9 team is one human officer and one trained police dog, they need a little more legroom. Therefore, many use SUVs instead. Those vehicles usually have special markings in addition to the standard departmental paint job, such as an added silhouette of a dog's head and/or a large K-9 emblazon. Departments with horse-mounted officers use pickup trucks and trailers to transport their mounts from stables to deployment areas, which means they are using one form of transport to haul another. However, these horses and dogs are not considered mere tools by their human partners; for the vast majority, the animal very nearly becomes a Non-Human Sidekick. Further, most states consider an assault against a police dog or horse a felony, and federal law enforcement animals are also protected by the Federal Law Enforcement Animal Protection Act.
- There are also other vehicle types for specialized purposes, such as large SUVs for rural departments, Priuses or electric cars for parking enforcement and city patrols, vans for evidence techs (and SWAT teams), and so forth. Jurisdictions with extensive waterfronts will have police boats of various kinds; agencies with lots of square miles to cover will have helicopters and possibly fixed-wing aircraft; and police motorcycle units are almost as common as Crown Vics. Some departments have bicycles as well; the belief is they provide as much community contact as old-fashioned walking the beat, but give the officer both more speed and the ability to cover a greater area. And, yes, the Segway is also in use by "real" police departments, not just mall cops.
- Third, Post 9/11, one trend police forces in general seem to be following is equipping themselves with secondhand military grade gear. Due to a number of anti-terrorism policies set forth by Congress, police departments may request to be equipped with surplus military gear such as body armor, assault rifles, and armored vehicles, to the point where some police departments have become virtually indistinguishable from a military unit. Any local police department can take advantage of this, regardless of location or size. While some people won't question the LAPD or NYPD getting better gear to protect their respective cities, they do question whether it's really necessary for a small town police department in the middle of Alabama to be packing assault rifles and MRAP vehicles designed to survive IEDs in Iraq, especially when they start using said gear to carry out arrests for relatively small offenses. This "militarization of the police" has not been without controversy.
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Normally, the law and police have power from the State in which they are in. State law authorizes local and city governments to form police departments and establishes their jurisdiction. Thus, most policing is from the city and county police forces. City police forces (the New York City Police Department, the Los Angeles Police Department, etc.) handle most crimes in their cities. They are headed by a Commissioner, Chief, or Superintendent, who is usually appointed by the Mayor. The Sheriff's office or department is the typical name for a county-level local police agency, and handles crimes where people flee between cities, or where the crimes take place in areas not incorporated into a municipality below the county level. The Sheriff is usually an elected office. Most of the Sheriff's force are deputies, which are hired positions. Sheriffs or county marshals almost always serve as the primary enforcement arm of the local courts, serving warrants, writs, evictions, and other court orders, and running the local jail system (in many places, these roles may be all that the sheriff is responsible for). Sheriffs are also commonly designated in many places by law as the county coroner, often a position called the "Sheriff-Coroner," and has responsibility for finding and properly handling unclaimed dead bodies in the county (and, very often, also running the local medical examiner's office). Sheriff's offices may also handle specialized and expensive law enforcement resources, like evidence laboratories, bomb squads, search and rescue teams, or SWAT teams and make these available to local police agencies too small to have their own versions of these. In some cases multiple cities may form metropolitan police departments that merge city- and county-level agencies into a single department with county-wide jurisdiction (the Las Vegas Metropolitan Police Department is an example, having been created by a merger of the Clark County Sheriff's Office and most of the local police departments in the Vegas metropolitan area, with the elected Sheriff of Clark County serving as the head of the department), or smaller cities may contract-out police services to larger neighbors including the Sheriff. In rural areas not large enough for their own police force and for crimes taking place on state highways, the state police or highway patrol has jurisdiction. Of course, this doesn't apply everywhere. In some places the police have completely supplanted the Sheriff as the primary law enforcement officer, in which case the Sheriff may shift into a role similar to the U.S. Marshals (see below) as an enforcement arm of the courts...or they may have had those duties assigned to the Staties or another agency, in which case they don't really serve much of a purpose but continue to stick around anyway. (Everyone in New York City knows about the NYPD, but 9 out of 10 New Yorkers probably don't know that the New York City Sheriff's Office still exists, let alone what they donote .) County sheriffs are traditionally elected officials in many states, usually as provided by state constitutions and county charters, so maintaining an elected county sheriff may be legally required even if their remaining duties are minimal or mostly ceremonial. Naturally, this varies depending on where you are, because if there is one thing Americans love, it is for every little town to have their own way of doing things and their own set of laws. Sheriff's departments are also often given jobs city police forces find too difficult or that don't fall clearly into any one agency's jurisdiction; e.g. the Los Angeles County Sheriff's Department polices Southern California's passenger railways, including the LA subway. Likewise, the San Francisco Sheriff's Department handles law enforcement and security for the civil and criminal courts, City Hall, the Emergency Communications & Dispatch center, San Francisco General Hospital, Laguna Honda Hospital, and several public health clinics, supplementing the San Francisco Police Department. Alternately, in many rural counties, especially in the south, the Sheriff's Department may be the most powerful local agency. This may be the case because the county has numerous towns too small to justify having their own police department, or one town that does support a police department but also a large county with a significant but widely dispersed population. In such counties, deputies may fulfill most or all of the roles local police are typically responsible for. Several distinctions typically exist between local and county hierarchies, as well. The sheriff is always an elected official, but the police chief may be appointed. Consequently, while the chief can be fired, the sheriff may require a staggering effort to remove from office sooner than the next election. The sheriff may also have far broader powers over his department; many sheriffs can and do set "morality guidelines" regulating everything from facial hair to cohabitation status (yes - a deputy can be legally discharged for shacking up without getting married in some counties), and may be able to fire deputies for any reason or no reason (by technically not firing them, but ending their contract of employment, as the sheriff may be able to deputize and release at his own discretion, without oversight), even if that reason is unbelievably stupid. By contrast, most chiefs are tightly bound by policies and regulations and have significant oversight. As the sheriff may also be responsible for the county jail, the coroner's office, issuance of various licenses and permits, serving warrants, and numerous other tasks, he is sometimes the most powerful public official in the county. In counties where both agencies have comparable powers and responsibilities, don't be surprised to see interdepartment rivalry, sometimes friendly, sometimes less so. Occasionally state departments get thrown into the ecosystem as well, and typically neither local department likes them for it. As far as an example of enforcement goes, the hierarchy for Beverly Hills in California is like this: Beverly Hills, then LA County Sheriff, then California; unless the miscreant flees from Beverly Hills to Malibu via non-county or state roadways. Then it is Beverly Hills, LAPD, California State, then Los Angeles County Sheriff (via contract with Malibu City). State and federal come later, depending on what the miscreant was up to. To put that in Layman's Terms, if you mess up in Beverly Hills and flee in any direction more than four miles, there will be up to six agencies trying to get an arrest statistic with you as the number.
State police agencies are responsible for apprehending criminals on State highways or across county lines, and also for investigating crimes involving state property and protecting state-owned facilities. ( Hawaii is the only state without its own state police agency.) In most of the States, they are also (and primarily) responsible for enforcement of traffic laws, and are tasked with patrolling the Interstate highways that pass through their particular state. The State Police can also be called in if there is a conflict of interest with the local police force or accusations of corruption. They are variously called the State Police, the State Troopers, the State Patrol, the Highway Patrol, or the State Highway Patrol. Most states also have a SBI, State Bureau of Investigations, which is an agency of (mostly) plainclothes officers whose primary duty is, natch, investigative work. These agencies also have a variety of names: (Name of state) Bureau of Investigation or Criminal Investigation Division (CID) are the most common. To make matters even more confusing, in some states these agencies are branches of the state police; in others they are different agencies under a single larger "department of public safety"; and in still other states they are completely separate. Most states typically also have separate fish and game agencies intended to protect the state's wildlife and enforce hunting, fishing, and conservation laws. A common situation in some smaller states is to give the state police agency primary responsibility for most homicide investigations. For example, the Massachusetts State Police handles all homicides occurring outside of Boston, Springfield, and Worcester (sorry, Jesse Stone). In Maine, the Staties investigate homicides occurring outside of Bangor, Portland, and Cabot Cove. In fiction, probably the best known examples of state police protagonists are the California Highway Patrol and, of course, the Texas Rangers. One often overlooked but major type of law enforcement agency that also operates at the state level is the corrections department that operates the state's prisons. Obviously, they have jurisdiction over prisons, which have the highest concentration of criminals, but these departments often also are responsible for managing convicted felons on probation or parole, and investigating criminal activities that are taking place both inside and outside prisons (e.g.: gang activity). This makes these very active and busy agencies, and often surprisingly large (the California Department of Corrections and Rehabilitation, for example, is actually the second-largest law enforcement agency in the United States after the NYPD).
For National laws, the Federal Bureau of Investigation (FBI) is the primary investigative arm of the United States Department of Justice (DOJ), serving as both the principal federal criminal investigative body and a domestic intelligence agency. Note that although they are the "investigative arm" of the DOJ, they don't answer to them. The Director of the FBI reports directly to the U.S. Attorney General (who is the head of the DOJ) and normally through him or her to the President of the United States. The reason it's part of DOJ is that the DOJ is the agency responsible for all litigation to which the federal government is a party,note prosecuting people who violate federal criminal law falls under the "litigation" description, and in the modern world they need people to go out and find the information needed to prosecute those violators. Or to be short: The original reason for the FBI is that DOJ's lawyers needed people to find information for them to actually convict people who were accused of breaking the law, and things kind of snowballed from there. It was founded in 1908 and became famous in the 1930s for its battles with bank robbers and kidnappers. Of the latter, the most infamous was probably "Machine Gun" Kelly; his (alleged) cry of "Don't shoot, G-Men!" gave the FBI a nickname that would last for decades. Of the former, "Baby Face" Nelson, "Pretty Boy" Floyd and John Dillinger were by far the most publicized. Almost immediately after the bank robber era ended, World War II engulfed the U.S. The FBI, following the lead set by British Intelligence, completely outclassed the Axis spy agencies; also, while the FBI did arrest German, Italian and Japanese "aliens" in America who were clear dangers to the war effort, the Director of the FBI vehemently opposed the mass internment of Japanese-Americans ordered by the Roosevelt administration. The latter fact tends to be overlooked in modern discussions of that Director. For nearly 50 years the FBI was headed by J. Edgar Hoover, who blurred the line between brilliant law-enforcement administrator and paranoid tyrant. When he joined the Bureau of Investigation, predecessor to the FBI, it was a practically powerless nonentity rife with corruption; from 1935 through the 1970s, he made it synonymous (to the vast majority of Americans) with effective, efficient and incorruptible law enforcement. He also made himself synonymous with the agency. After his death, some of the luster was peeled away; it was revealed that, without particular regard for Constitutional niceties, he tapped phones and assembled files on...well, we can't really be sure about how many people he was spying on, since the files were all destroyed after his death. No Director since has achieved his level of fame, though the Bureau has slowly reclaimed much of its previous good reputation. The FBI is automatically called in if a crime crosses state lines, or in special cases for crimes that do not but that fall under federal jurisdiction for one reason or another. There are currently at least 5,000 specific federal offenses, so an exact enumeration of what might bring in the FBI is beyond the scope of this article or, indeed, all the combined contributors to this wiki. However, some general guidelines, important specifics, and interesting cases can be noted:
- A federal crime typically involves something that crosses state lines or involves multiple states or interstate commerce, or one that interferes directly with the federal government's business—assaulting a federal employee in official business, crimes on federal property, destruction of mailboxes... what? You read that right, that's a federal matter (mailboxes deal with the mail, which is handled by the US Postal Service, which is a federal government corporation created by Congress' power under Article I, Section 8, Clause 7 of the Constitution to create a post office). Good luck actually getting the FBI to come investigate someone messing with your mail, but legally it is their problem.
- Although they do investigate serial mailbox destruction as it is a sign of tampering with the mail and, also, crimes like identity theft and destruction of evidence.
- And as far as mailboxes, most people don't realize that the Post Office has its own police force so chances are, they handle it first before passing it on to the FBI.
- The FBI also may be called in to investigate local and State police if there is a conflict of interest or accusations of corruption. National law gives them the power to investigate if anyone's "Civil Rights" are violated. Since one of the rights is the right to a fair trial, this automatically covers corruption or brutality.
- Since copyright falls under federal law, the FBI puts warnings that they will raid copyright infringers and slap them with heavy fines and prison sentences on every videotape and DVD sold in America. How much they actually do this depends upon the film industry's generous bribes, er, campaign contributions to members of Congress this term, and, also, the scale of the violation— basically, if you make a business out of counterfeiting Blu-Rays, sooner or later the G-Men will show up.
- The FBI made its rep battling bank robbers and kidnappers like John Dillinger and Baby Face Nelson. The quantum leap forward in automotive technology in the late 20s and early 30s allowed criminals to rob or kidnap in one state and avoid prosecution by simply hotfooting it across a state line. To combat this, Congress passed the Federal Kidnapping Act of 1932 (in response to the infamous Lindbergh kidnapping), and the first of several laws against bank robbery in 1934 (most U.S. banks are federally-insured). Now the FBI is automatically called in in such cases.
- In general the FBI's jurisdiction often has it going after the "big fish" - Mafia families and the like. They usually don't bother with the small fry, leaving the local police to handle them, which is just as well, since they don't have jurisdiction anyway. The FBI is however heavily reliant on local police departments for knowledge of their own jurisdictions and often manpower. The Bureau typically has more money and resources than it has people in a particular city or townnote , which means that, usually, both the FBI and local police have an incentive to work together where they can. Unlike in fiction the FBI (and other federal law enforcement agencies) normally cannot unilaterally "take over" a case from state or local law enforcement and prevent them from investigating unless there are extremely unusual circumstances. State and local agencies are created and operate under the law of the states they're located in, which means they're not subordinate to the FBI or the federal government.
- A little known fact is that the FBI has jurisdiction over US diplomatic facilities, as they are considered to be part of the United States. The FBI has over 50 overseas offices situated in various US embassies and consulates. They are also responsible for investigating attacks on any of these facilities.
- There are quite a few people (including Americans) who tend to conflate the FBI with the CIA, since they're both major federal goverment bodies that are supposed to stop "bad guys", can cause govermental paranoia, and have three letter acronyms. The CIA doesn't deal with crime at all, however; they spy on foreign nations instead. The FBI does have responsibility to catch foreign spies in the US, but they don't have any James Bond-types to do it with.
- During WWII, G-Men operated undercover in Latin America keeping tabs on the Germans (remember Cary Grant in Notorious). The CIA took over this function after 1947 (but probably became less focused on the Germans).
The United States Marshals Service (USMS) is the enforcement arm of the federal courts, responsible for serving warrants and other court orders, apprehending wanted fugitives, providing protection for the federal judiciary, transporting federal prisoners, protecting endangered federal witnesses (More commonly known as Witness Protection) and managing assets seized from criminal enterprises. The US Marshal's Service supposedly is responsible for a narrow majority, about 55%, of all arrests made by federal law enforcement. For more information, and a list of fictional uses, see U.S. Marshal.
The guys in suits who guard the President, Vice President, their immediate families, the Secretary of Homeland Security and other officials, wearing Sinister Shades doing it. The United States Secret Service (USSS) also investigates financial crimes such as counterfeiting, credit card fraud, computer crimes, etc., but aren't terribly well known for that, although that was their original role when they were created in 1865. They didn't get their protection role until 1901, after the assassination of President William McKinleynote . Formerly under the Treasury Department, they were moved to Homeland Security post-9/11. Since then, the Secret Service is also tasked with handling security for particular "National Special Security Events," like political conventions, State of the Union speeches, even the Olympics, that might be a target for terrorists. Who gets Secret Service protection is controlled by Congress. In addition to the US officials named above, the Service also guards heads of state from other countries when they visit the United States. Former Presidents and their spouses receive protection for the remainder of their lives note —although they can voluntarily surrender such; Richard Nixon was the first to do so — and children of former Presidents receive it until they are 16 years old. Major Presidential candidates can get it fairly early on in the US primary process. There are no hard rules for when candidates are given protection; the metric is a very fuzzy "how good are their chances of winning the election and how many cranks have started threatening them". Barack Obama held the record for being granted Secret Service protection the earliest of any Democrat candidate for President note , while Ben Carson and Donald Trump currently co-hold the record for Republicans. While the plainclothes agents are, ironically, the most familiar to the public, the Secret Service also provides guards to protect the White House. They wear uniforms and carry firearms the same as any other police officer, have patrol cars for traveling near the White House, and are known as the "Secret Service, Uniformed Division." These guys also travel along with the President providing additional security and firepower as part of a "Counter-Assault Team," basically a SWAT team that exists to fight off an organized, armed attack on the President. The USSS has the best rate of capturing criminals of any American law-enforcement organization. Due to the nature of counterfeiting, it is a crime for losers (your odds of being caught if you decide to do it in a big way are over 90%), unless you are an actual enemy nation. (Germany started counterfeiting the dollar in WWII after they had their fill of fake pound notes. Modern-day counterfeiters include Iran and North Korea.) They have, by law, access to the cooperation of any and every other part of the Federal government, including the military, in fulfilling their protective duties. In fiction: Probably the best known example focusing on the USSS is the Clint Eastwood movie In the Line of Fire. The Secret Service is also Pete's and Myka's original agency on Warehouse 13.
The Bureau of Alcohol, Tobacco, Firearms and Explosives (abbreviated ATF or BATFE) handles exactly what it says on the tin. One of its predecessor agencies, the Bureau of Prohibition, was home to Eliot Ness's "Untouchables." Started out in the Treasury Department (hence references to Ness & co as "T-Men" in stories, or at least in Crossword Puzzles), but currently under DOJ. (Somehow "J-Men" hasn't really caught on.) The ATF has been a highly controversial agency, in part for its role in the middle of American Gun Politics, as well as several colossal blunders over the years (including their involvement in the Ruby Ridge and Waco sieges in the 1990s, as well as, more recently, the Operation "Fast and Furious" gunrunning scandal). Cynical observers of US politics have observed however that keeping the agency around, in a weakened and discredited state, has been more politically useful to gun rights proponents, such as the NRA, than seriously reforming the agency or abolishing it and giving its duties to another agency, like the FBI. The areas it's responsible for are listed in the order they were given to the Bureau. When "Explosives" was added in the late 90's, they slapped it on the end and passed on the golden opportunity to become The Bureau of FATE. Other US law enforcement agencies have not been so stuffy; see "Immigration" below. The ATF is also Steve Jinks's original agency on Warehouse 13.
The Drug Enforcement Administration (DEA) is also exactly what it says on the tin. The DEA is unique in that it also administers and tracks doctors' authority to prescribe legal drugs as well as both drug trafficking inside the USA and overt and covert actions in foreign nations. It is the only organization besides the CIA that generally does undercover actions in other nations, and is the only organization period that can do that and work domestic issues. It is the only civilian agency anywhere in the world that flies helicopter gunships. Also under DOJ. DEA does a lot of work on "source control" of precursor chemicals used to make or refine drugs, as well as a lot of undercover work. In fiction, the DEA has never achieved the fame of the FBI although it has fared somewhat better than the ATF. Its most notable appearance is probably in Breaking Bad, which featured a DEA agent, Walter White's brother-in-law Hank Schrader, as something of a Hero Antagonist as Walt built up his meth empire. Remember—it's the Drug Enforcement ADMINISTRATION,not the Drug Enforcement Agency. Even journalists get that one wrong.
Customs and Immigration
U.S. Immigration and Customs Enforcement (ICE) is also exactly what it says on the tin. It used to be a few separate agencies, but they've been merged, split, and shuffled around a lot in the last few years. Right now they're in Homeland Security. It may also be referred to by Spanish-speakers (and Spanish-speaking characters) as "La Migra", a nickname inherited from the previous agency, the Immigration and Naturalization Service (INS), which was abolished with the passage of the Homeland Security Act in 2002. It is, however, a Discredited Trope since many works of fiction continue to use the name. ICE is the second-largest criminal investigative agency of the federal government (after the FBI), the largest within the Department of Homeland Security, handles a large amount of collateral national security, anti-terrorism, and other investigation work related to customs and immigration, due to the matters they handle, tend to be the one most likely to be spotted by the average person in an American city on a day-to-day basis. The Border Patrol is actually part of Customs and Border Protection (CBP), an agency that's separate from ICE because they have slightly different missions; CBP works mainly at the border and at border crossings. They are also charged with preventing illegal things from crossing the border whereas ICE is responsible for dealing with contraband and illegal entrants after they have crossed.
The U.S. Coast Guard used to be part of the Department of Transportation but after 9/11 was moved to the Department of Homeland Security. Originally, the Coast Guard was a Treasury Department agency concerned with stopping smugglers. Its additional duties became ocean/waterways safety and rescue, as well as checking shipping. During wartime, the Coast Guard could be moved to the Department of Defense, serving as part of the US Navy while maintaining its status as an independent service, and would also handle coastal and waterway defensenote . Since the "War On Drugs", the Coast Guard began to change and now spends 95% of their efforts in drug interdiction. US law states that anything between the coast and 3 nautical miles (5.6 km) outnote is state territory, while beyond that out to international waters is federal territory. Coast Guardsmen also serve on Navy and Marine ships in LEDETs (Law Enforcement DETatchments) to handle any civilian-type boardings and such. The Navy and Marines both act as if subject to Posse Comitatus, while the CG is not and does not. Port Security Units are also deployed just about everywhere as, well, Port Security.
The National Guard
The National Guard aren't really a police force, more reservists for the Yanks with Tanks. Each state has an Air National Guard, who play a part in US air defense and get to fly F-16s. 20 Presidents have been in the National Guard at some point in their lives. The main role in terms of law enforcement is in the field of riot control. The Posse Comitatus Act of 1878 prohibits the use of the regular military in domestic law enforcement (except for when ordered by the President under exceptional circumstances, such as the Insurrection Act), but does allow the National Guard to be used. The Guard's other main role has nothing to do with law enforcement at all — they're typically called out for disaster relief operations when a state gets hit by something really nasty. The National Guard is run by state and is under the authority of the Governor of that state. The President can, however, "federalize" a state National Guard, placing them under his or her control. The most notable case (other than wartime mobilizations) was in 1957, where Arkansas National Guard troopers were taken into federal command to enforce racial desegregation in Little Rock schools.
He is vengeance. He is the night. He has no jurisdiction. However, any individual, anywhere in the United States, including a civilian, may arrest a person who commits a felony in their presence. Usually they can also arrest for a misdemeanor committed in their presence as well. Of course, some random civilian telling you to "stop right there!" lacks the oomph that hearing it from a person with a badge does... and random civilians also tend to not have a gun to back up the demand and handcuffs to make sure you stay stopped, so civilian's arrest is nearly always treated as a joke. Ancient right going back to the days of King John and the Magna Carta (note to British readers: you have this right, too) or no, it's the kind of thing that just makes you look kind of ridiculous unless you happen to be able to back it up. If you're going to try it, be prepared to physically restrain the guy you're arresting, and be prepared for him to fight back. Alternatively, you could take out your cellphone, dial 911, and have the trained people who get paid for doing that sort of thing handle it. Guess which option most Americans choose. Aside from the issue of needing to make the person submit to a citizen's arrest, once you have been considered to legally do so, you're now responsible for that person... Which makes it even less appealing. Also, if you're wrong, the person you "arrested" may (depending on the circumstances) be able to sue you for false imprisonment. Which makes it really unappealing.
Naval Criminal Investigative Service. Half civilian, this organization investigates crimes related to the US Navy and Marine Corps - any death on a vessel, aircraft or facility. NCIS is a primarily civilian agency that reports directly to the Secretary of the Navy, who is a civilian appointed by the President working directly for the Secretary of Defense, and is thus above/outside both the Navy and Marine Corps service chains of command. However, NCIS works closely with Marine Corps and Navy personnel serving as military police and naval security forces, as well as with other civilian police officers who serve as law enforcement officers at some naval installations. Obviously, due to its relationship with the naval service, it frequently operates abroad as well, often performing investigations and security evaluations of foreign ports that US ships might call to. They conduct criminal investigations under the provisions of the Uniform Code of Military Justice (UCMJ) and other federal statutes. Analogous to the Law & Order TV-series: NCIS is the "Law" part, while JAG is the "Order" part. For those wondering why a military branch needs a civilian agency for criminal investigation, there are three reasons:
- One, since they work with the service but are not part of the military chain of command, it gives them a certain flexibility when dealing with military personnel as they don't have to play as many games with rank.
- Two, the Director and Special Agents don't depend on military officers for promotions and future assignments. This is pretty much the reason why NIS was reorganized into NCIS in 1992, following the botched Tailhook investigations.
- Three, civilian control of the military have strong traditions in the US, but equally strong is the respect for military professionalism and the recognition of the military as a unique separate society. A specialized civilian agency is the tradeoff solution.
All five branches of the US armed forces have some kind of military police force.
- The US Army force is the M.P.s, short for Military Police.
- The US Navy police is the M.A.s, short for Master-at-Arms. Those assigned to duty on land are also known as the Shore Patrol.
- The US Air Force law enforcement branch is the S.F.s, short for Security Forces (not Special Forces).
- The US Coast Guard has M.E.s, which is short for Maritime Enforcement specialists.
- The US Marine Corps also has M.P.s. Since the Marine Corps is also part of the Navy, M.A.s may find themselves dealing with miscreant Marines as well.
Despite the name, they don't work for the U.S. Marshals. The Federal Air Marshal Service, commonly referred to as the Air Marshals, are a federal law enforcement agency supervised by the Transportation Security Administration, or TSA. They were actually founded in 1968 and existed as a very minor subset of Customs and Immigration. All that changed on September 11, 2001. After 9/11 the FAMS was massively expanded and moved into the newly created TSA. They carry concealed weapons and sit on board regular flights while posing as normal passengers. Unlike most branches of law enforcement, they act preemptively. Air Marshals go where no crime has been committed, so that they will be in place to respond should anything (like, oh let's say, 3 or 4 men with box cutters attempting to take control of the plane) occur.
Other police forces
Many government agencies (federal and state) have their own police forces patrolling their own property or dealing with criminal activities involving their own activities. How many is yet another source of controversy; one source estimates that at least 70 agencies with sworn police powers operate out of the various Federal departments alone. The Inspector General Act of 1978 created Inspector General offices in departments and agencies across the federal government—73 of them as of 2015—each of which is empowered to investigate criminal activity, waste, fraud or malfeasance within their departments, and all of which employ criminal investigators with badges and guns. One large yet relatively unknown example is the United States Postal Inspection Service, which investigates mail fraud, protects postal facilities in high crime areas, and protects sensitive mail deliveries. The IRS, which is the branch of the Treasury Department that collects federal taxes, has its own Criminal Investigation Division (IRS-CI) which has exclusive authority over criminal enforcement of the Internal Revenue Code, which makes it also a very active agency. The overabundance of police agencies, as you might expect, leads to some jurisdictional absurdity; the corner of First Street and East Capitol in DC sits between three government buildings (the Capitol, the Supreme Court, and the Library of Congress), each of which has its own police force separate from the DC Metropolitan Police, who patrol the intersection itself. It also leads to other interesting questions; the 2010 purchase of short-barreled shotguns by the Department of Education (for their fraud investigators) has sparked reactions ranging from humorous to paranoid. Some non-governmental entities, like universities and railroads, have also been given authority to establish forces on their properties with full police power — including, of course, the legal right to carry and use firearms. The decline of importance in the public eye of the railroads in America is probably why no major works of fiction deal with railroad police, but they are trained and sworn law enforcement officers with both state and (limited) federal authority. Campus cops also rarely appear in fiction unless it's as the butt of a joke, but you have to learn the trade somewhere. Still, in some cases campus police are a force to be reckoned with. For example, the University of California system's force covers all 11 UC campuses, and the California State University system's officers are responsible for all 24 schools. In addition, due to the fact that most public universities in the US are technically State land, campus police forces are drawn from the State Highway Patrol and have the training that one would expect for State police. note The Hyde Park neighborhood of Chicago, where President Barack Obama maintains a home, is widely regarded as one of the safest neighborhoods on the traditionally crime-ridden South Side of Chicago, due in part to the fact that the University of Chicago located there has its own police department which patrols the neighborhood along with the Chicago Police Department. The distinction between "campus security" and "campus police" is sometimes lost on new students...until they drunkenly assume they don't have to listen to a "rent-a-cop." Hilarity Ensues. As the day-to-day work of such a limited police force will probably not be matters of life and death, if they show up in fiction, it'll probably be to get in the way. Of course, the day-to-day work of most police officers isn't life or death either, so there may be room for creative exploration here.