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 West Virginia (WV), criminal procedure is governed by a combination of state statutes, the West Virginia Rules of Criminal Procedure, and federal laws, including constitutional protections afforded to defendants. These procedures outline the steps from the initial investigation of a crime to the arrest, charging, trial, and potential conviction or acquittal of a defendant. The U.S. Constitution, particularly the Fourth, Fifth, Sixth, and Fourteenth Amendments, provides the foundation for rights such as protection against unreasonable searches and seizures, the right to due process, the right to a speedy and public trial, the right to counsel, and protection against self-incrimination. West Virginia's rules and statutes are designed to ensure that these constitutional rights are respected throughout the criminal justice process. Additionally, state and federal court opinions interpret and apply these rights to specific cases, further shaping the practice of criminal procedure in West Virginia.