If a crime is brought to the attention of federal authorities, whether by a victim of the crime or a witness to it (e.g., a bank robbery), a federal law enforcement agency will undertake an investigation to determine whether a federal offense was committed and, if so, who committed it. Two points should be kept in mind:
First: Not every crime is a federal offense. For example, murder is a crime in all 50 states, but it is not a federal offense unless, for example, a federal official is murdered while performing official functions. Robbery also is outlawed in every state, but it is not a federal offense unless there is some connection with the federal government, such as the robbery of a federally insured bank. Federal law enforcement agencies will investigate a crime only if there is reason to believe that the crime violated federal law.
Second: The nature of the federal offense may determine which agency undertakes the investigation. Not every federal law enforcement agency has the responsibility to investigate every crime. For example, the Secret Service is responsible for investigating counterfeiting of currency, and the FBI is the lead federal agency for terrorism cases. This assignment of functions helps different agencies develop expertise, but it also means that federal law enforcement agencies are not like local police forces—they do not each handle whatever federal crime comes their way.
If the agency concludes that a crime was committed and identifies a suspect, federal law enforcement officers (known as special agents) may make an arrest without obtaining an arrest warrant; may obtain an arrest warrant for a named person; or, in some circumstances, may delay making an arrest in order to obtain additional evidence proving the suspect’s guilt.
In the case of federal offenses that are colloquially known as white-collar crimes (e.g., violations of the federal securities laws), agents often will need to obtain documents from suspects and innocent parties as part of the investigation. To do so, the agents can apply for a search warrant from a magistrate (or judge) to search a particular site for relevant evidence. Alternatively, the agents can request a subpoena from a grand jury.
A grand jury is an impartial body of citizens drawn from the community that has the responsibility to investigate whether a crime has been committed and by whom. In order to make that determination, a grand jury may issue subpoenas to whoever may have evidence relevant to the grand jury’s investigation. As part of its investigation, the grand jury also has power to compel testimony, including the testimony of a crime victim. If the grand jury concludes that there is probable cause to believe that a particular individual committed a crime, the grand jury will issue a charging document known as an indictment. Whenever a grand jury is involved in an investigation, the agents will work closely with an attorney from the U.S. government, either from the local U.S. Attorney’s Office or the U.S. Department of Justice, before making an arrest in order to determine whether a crime was committed and, if so, who is responsible.
Arraignment is the stage at which the defendant formally is told what the charges are and is given a copy of them. The defendant then enters a plea responding to those charges, which generally is not guilty or guilty. If the defendant and his attorney already have negotiated with the prosecutor and have agreed upon a plea bargain, the defendant may enter a guilty plea at the arraignment as part of the plea bargain. Plea bargaining is discussed below.