Criminal procedure is the process related to the investigation, arrest, charging, and conviction or acquittal of a criminal defendant. Much of criminal procedure is comprised of processes and rules through which the government (state, federal, or municipal) enforces substantive criminal law and through which a criminal defendant’s Constitutional and other rights are protected.

The law of criminal procedure is primarily located in the applicable state or federal rules of criminal procedure and state and federal court opinions interpreting and applying Constitutional and other legal rights.

In Kansas, criminal procedure is governed by a combination of state statutes, the Kansas Code of Criminal Procedure, and federal laws, as well as the U.S. and Kansas Constitutions. These laws and rules outline the steps and legal protections involved in the criminal justice process, from investigation and arrest to trial, sentencing, and appeals. The process is designed to ensure that the rights of the accused are protected throughout, including the right to a fair and speedy trial, the right to counsel, and protection against self-incrimination and unreasonable searches and seizures. Kansas courts interpret these laws and rules, and their decisions contribute to the body of precedents that shape the application of criminal procedure. Additionally, the Kansas Rules of Criminal Procedure provide specific guidelines for various stages of the criminal process, such as arraignment, pretrial motions, and the conduct of trials. These rules are meant to ensure that both the state's interest in enforcing criminal laws and the defendant's constitutional rights are balanced and upheld.