The criminal justice system keep us safe from criminals. When a person arrested by a policeman with a badge and is accused of a crime that person becomes a defendant. Police usually carry guns. A detective usually investigates the crime. Police and detectives usually put handcuffs on the defentant to make sure he cant escape. Later at the station they will take his fingerprints. At the trial, the defendant has a defense attorney to defent him in front of the judge. Both the prosecuter and the defense can call witnesses. If the defendant is found guilty, he will go to jail.
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