In a criminal case the state prosecutes the accused person for committing a crime or breaking the law. ‘Prosecutes’ means the state makes a charge against someone. If the court finds the person guilty, the person can be sent to prison, or fined, or punished in some other way. Examples of different crimes and breaking the law include rape, public violence, assault, theft and trespass,
Usually the state is not the complainant (the one making a charge). The state prosecutes, but any person or individual can be the complainant and lay a charge against another person or against the state.
A criminal case can be brought against anyone who has broken the law, including a person who works for the state, such as a member of the police or defence force. So if, for example, you are unlawfully assaulted or shot by a member of the police or defence force you can bring a criminal case against them.
When a case is brought before a magistrate, the prosecutor must prove beyond a reasonable doubt that the accused committed the offence. ‘Beyond a reasonable doubt’ is the standard that must be met by the prosecution’s evidence in a criminal prosecution: that no other reasonable explanation can be drawn from the facts except that the defendant committed the crime, in this way overcoming the presumption that a person is innocent until proven guilty.