Federal Court System
United States Marshall
These people make arrests, collect fines, take the convicted to prison, protect jurors, keep order in court, and serve subpoenas ordering people to court.
The requirements to become a Marshall are: US citizen, between ages 21 and 36, have a bachelor's degree, 3 years of work experience, background check, excellent physical condition, and a 17 1/2 week rigorous training.
United States Attorney
They are a government lawyer who persecute people accused of breaking federal laws. They look into charges and present the evidence in court, represent the US in civil cases involving the government, and receive oversight, supervision, and administrative support services through the Justice Department.
They decide whether accused people should be held in jail or released on bail. They are needed in each district court and do much of the judge's routinely work. They also hear preliminary evidence and determine whether the case should go to trail or not.
This means you can serve for however long you want. All justices serve life terms.
The judge's opinion explains the legal thinking behind the court's decision in the case. The opinion then sets the precedent which is a model for other judges to follow in making their own decisions on similar cases.
To remand a case means to send it back to the lower court to be tried again.
There are 12 districts/geographic areas of a US Court of Appeals, each called a circuit. The 13th appeals court is the Court of Appeals for the Federal Circuit and has nationwide jurisdiction.
The appeals court has an appellate jurisdiction, meaning they have the authority to hear a case appealed from a lower court.
District courts have original jurisdiction, meaning they have the authority to hear the case for the first time.
District courts are the lowest level of Federal Government where trials are held and lawsuits are begun. They have original jurisdiction and hear both civil and criminal cases. This is the ONLY federal court that involve witnesses and a jury.
Court of Appeals
The Court of Appeals for the Federal Circuit is the 13th appeals court. It has nationwide jurisdiction and does not hold any trials.