A prosecutor is the government's attorney in a criminal case who represents the people, such as a District Attorney, States Attorney, U.S. Attorney, Attorney General, Solicitor General, or special prosecutor. A prosecutor may investigate certain criminal offenses on his own initiative, or at the request of a government officer or government body.
A prosecutor works with law enforcement officers to ensure that justice is done. He or she makes the decision whether or not to bring charges for a crime and against whom the charges will be brought. The prosecutor must persuade the jury or judge "beyond a reasonable doubt" of every fact necessary to constitute the crime charged. The prosecutor must both refrain from the use of improper methods calculated to produce a wrongful conviction and must use every available legitimate means to obtain just convictions.