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 Colorado, criminal procedure is governed by a combination of state statutes, the Colorado Rules of Criminal Procedure, and federal law, including constitutional protections. These procedures outline the steps from the initial investigation of a crime to the arrest, charging, and eventual trial of a defendant. They ensure that a defendant's rights, such as the right to a fair trial, the right to counsel, and protection against self-incrimination, are upheld throughout the criminal justice process. The Fourth Amendment's protection against unreasonable searches and seizures, the Fifth Amendment's protection against self-incrimination, and the Sixth Amendment's guarantee of a speedy and public trial by an impartial jury are particularly relevant. Colorado's rules also detail procedures for pretrial motions, plea bargaining, and the appeals process. The interpretation and application of these rights are continually shaped by state and federal court rulings.