How high in the pecking order of US law enforcement are they?
Are they above the FBI, CIA, State Police,Secret Service and so on and so forth.
In the film The Fugitive Gerard seemed to take over from the police who were first on the scene of the crash but it wasn’t made clear who was originally in charge
First, the CIA is not a law enforcement agency, but an intelligence agency. They are responsible for spying on foreign powers and committing espionage in foreign countries. (They are not supposed to perform these activities within the US, but seem to get in trouble for doing so every few years.)
The FBI is the primary federal law enforcement agency in the US and is responsible for enforcing most federal laws. It is an executive-branch agency within the Department of Justice. In addition to having a large number of agents (who are basically very well-trained detectives) they also run the nation’s most sophisticated crime and forensics labs, which often provide their services to state and local police forces who ask for help.
The US Marshals Service is a specialized federal law enforcement agency also within the Department of Justice. The primary purpose of the Marshals is to enforce and protect the US federal courts. When a federal court issues an order to seize property, the Marshals are the ones who seize it, for example. When a federal court needs extra security, the Marshals provide it. When a federal witness is threatened with being whacked by the Mob, the Marshals Service puts them in the Witness Protection Program, which they run. And when fugitives from the federal courts go on the lam, the Marshals are the primary guys responsible for tracking them down. (They also lend their expertise to state fugitive cases when they are asked.)
Within the federal government, no particular law enforcement agency is “above” any other one, but they have specific jurisdictional duties and expertise. The Secret Service, in addition to protecting the President and other people, is also responsible for investigating counterfeiting and computer crimes, due to their history of being part of the Department of the Treasury. (Counterfeiting was their original mandate; bodyguarding was added later.) The DEA is responsible for investigating federal-level drug crimes and drug operations in foreign countries (generally with the cooperation of foreign governments.) The ATF (also a former Treasury Department agency) is responsible for investigating illegal guns, explosives, and unlicensed alcohol and tobacco distribution (they get this authority because they are responsible for collecting the taxes on these things.) The IRS has an enforcement bureau which investigates criminal breaches of income tax laws, and so on.
Obviously, there’s potential for a lot of overlap. Federal agencies often work together on joint operations for large cases; these are usually run by the FBI since they have the expertise in large, complex law enforcement operations, and the more specialized agencies provide their expertise for their particular aspects of the case.
Don’t federal law enforcement officials have the authority to take over cases where a federal law is violated or the crime has an interstate character? Also, while no agency is “above” another, turf wars are not unheard of. My wife’s aunt who is a former LEO in Colorado told me the joke about the FBI is that it stands for “Famous but Incompetent”. Is there some sort of informal hierarchy among agencies?
Now you’re talking about the difference between state and federal law enforcement, which gets more complicated.
In general, the FBI will take over a state criminal investigation in two circumstances:
The crime involves the breaking of a federal law (anything happening across state lines is a good place to start, potential violations of federal Civil Rights laws are another)
The FBI is asked to investigate the case by the relevant state authorities. (Corruption investigations into local police forces are a good example, as are serious crimes like murder or arson sprees where the local cops may not have enough expertise to deal with it in a timely manner.)
The popular movie scene where The Feds show up and declare “I’m Special Agent Character Actor and I’m taking over this investigation!” generally don’t happen that way in real life.