Federal crimes are any infraction of federal law and legal code. They can range from mail fraud to identity theft, drug trafficking to gun licensing violations, and immigration fraud to illegally downloading songs and movies on the internet. Federal crimes are investigated by government agencies such as the FBI, IRS, or DEA. Federal criminal cases are vastly different from other types of criminal cases. The rules of procedure are unbending; the charges are usually complex; and the penalties are severe.
In the American system of government, states have some areas of responsibility for enforcing criminal laws and the Federal government has other areas. Sometimes the areas overlap and the two government agencies then decide who will take responsibility. Federal crimes are generally more serious than crimes charged in state courts. And the penalties in federal cases are generally more harsh — there are many offenses which carry a mandatory sentence of five or ten years in prison. Many crimes can be charged in either state OR Federal court (or even in both courts, however that doesn’t happen very often) and the consequences of being charged in Federal court are serious.