The Judicial Branch of the government is made up of judges and courts. Federal judges are not elected by the people. They are appointed by the president and then confirmed by the Senate.
There is a hierarchy of federal courts in the United States. At lowest level are 94 U.S. District Courts which cover different regions of the country and handle most federal cases. Above the District Courts are the 13 Courts of Appeals. At the top of the Judicial Branch is the Supreme Court. The Supreme Court has the final say.
The United States Supreme Court Building
Federal judges are appointed for life. They can only be removed from office by death or by impeachment from Congress. This is to allow judges to make decisions based on their conscience and not on what they feel they need to do to get elected.
The job of the courts is to interpret the laws of the Congress. They do not make laws. They also only make decisions on actual cases where someone has shown that they have been harmed.
The Supreme Court
The highest court in the United States is the Supreme Court. The Constitution doesn't say how many Supreme Court Justices there should be. There have been as few as 6 justices in the past, but since 1869 there have been 9 justices.
The President nominates all the Supreme Court members and the Senate confirms them. They hold their offices for life.
The Supreme Court doesn't have a lot of trials. What they mostly do is review cases that have been appealed from the lower courts. Not all cases that are sent to the Supreme Court are reviewed. Around 7,500 requests are sent to the Supreme Court each year and they only consider around 150 important enough to review.
The Judicial Process
The Constitution states that every person has the right to a fair trial before a competent judge and a jury of their peers. The Bill of Rights adds to this guaranteeing other rights such as a speedy trial, the right to legal representation, the right not to be tried for the same crime twice, and protection from cruel punishments.
Once arrested for a crime, the accused will get to appear before a judge to be charged with the crime and to enter a plea of guilty or not-guilty.
Next the accused is given a lawyer, if they can't afford their own, and is given time to review the evidence and build up their defense. Then the case is tried before a judge and a jury. If the jury determines that the defendant is not-guilty, then charges are dropped and the accused goes free. If the jury has a guilty verdict, then the judge determines the sentence.
If one side feels that the trial wasn't handled correctly or fairly, they can appeal to a higher court. The higher court may overturn the decision or keep it the same. The highest court is the Supreme Court. There is no appealing a Supreme Court decision.