The prosecutor must convince the judge or jury hearing the case that the defendant is guilty “beyond a reasonable doubt.” This standard is very hard to meet. (By contrast, in noncriminal cases, such as an accident or breach of contract, a plaintiff has to prove her case only by a preponderance of the evidence — just over 50%.)
As a practical matter, the high burden of proof in criminal cases means that judges and jurors are supposed to resolve all doubts about the meaning of the evidence in favor of the defendant. With such a high standard imposed on the prosecutor, a defendant’s most common defense is to argue that there is reasonable doubt — that is, that the prosecutor hasn’t done a sufficient job of proving that the defendant is guilty.

Criminal procedure is the adjudication process of the criminal law. While criminal procedure differs dramatically by jurisdiction, the process generally begins with a formal criminal charge with the person on trial either being free on bail or incarcerated, and results in the conviction or acquittal of the defendant.

The rules of criminal procedure are extremely important to defendants because they are designed to guarantee constitutional due process to those individuals charged with a crime. Criminal convictions can carry severe consequences, including: Paying steep fines and court costs.

A criminal case usually gets started with a police arrest report. The prosecutor then decides what criminal charges to file, if any. Some cases go to a preliminary hearing, where a judge decides if there is enough evidence to proceed. Cases can also start when a grand jury issues a criminal indictment.