Glossary
Criminal case
A case where the government accuses someone of breaking a criminal law: something serious enough that the punishment can include fines, probation, jail, or prison. The defendant has constitutional protections that don't exist in civil cases.
In a criminal case, the government: represented by a prosecutor: is one of the parties. The defendant has the right to a lawyer (provided by the court if they can't afford one), the right to remain silent, and the right to a jury trial. The government has to prove guilt "beyond a reasonable doubt," which is the highest standard in U.S. law.
Criminal cases are filed by the government, not by victims. A victim can report a crime and may testify as a witness, but they don't control whether the case moves forward. That's the prosecutor's call.