Criminal Procedure Law

The criminal justice system in the United States is an adversarial system, meaning the prosecution (representing the government) and the defense (representing the accused) argue their cases before a judge or jury. This system operates according to rules found in federal laws (like those in Title 18 of the U.S. Code and the Federal Rules of Criminal Procedure) and similar laws in each state. These procedures aim to protect the constitutional rights of individuals at every stage, from investigation and arrest to trial and appeals.

Constitutional Protections: Safeguarding Individual Rights

The U.S. Constitution provides crucial safeguards for criminal suspects and defendants. These protections are designed to limit government power and prevent abuses of individual freedoms. Most of them come from the Fourth, Fifth, Sixth, and Eighth Amendments, which are part of the Bill of Rights.

What Does the Fourth Amendment Cover?

The Fourth Amendment protects people from unreasonable searches and seizures. A "search" occurs when the government intrudes on someone's reasonable expectation of privacy. A "seizure" occurs when the government takes control of a person or their property. Generally, law enforcement needs a warrant issued by a judge based on probable cause to conduct a search or make an arrest. "Probable cause" means a reasonable belief, based on specific facts, that evidence of a crime is located in a particular place or that a specific person committed a crime.

Evidence obtained without a valid warrant, when one was legally required, may be excluded from trial under the "exclusionary rule." There are exceptions to the warrant requirement, such as when evidence is in plain view, in emergencies, when someone voluntarily consents to a search, or when a search is conducted as part of a lawful arrest.

How Does the Fifth Amendment Protect You?

The Fifth Amendment provides several key protections. It guarantees the right to remain silent, meaning individuals cannot be forced to testify against themselves. This is often referred to as "pleading the Fifth." It also guarantees the right to an attorney once someone is in custody or formally charged. If a defendant requests a lawyer or chooses to remain silent, police questioning must stop. The Fifth Amendment also prohibits "double jeopardy," which means a person cannot be prosecuted multiple times for the same offense.

What Does the Sixth Amendment Say?

The Sixth Amendment guarantees the right to a speedy and public trial, the right to confront witnesses against you, and, in many cases, the right to a trial by jury. It also ensures the right to an attorney. This means that individuals facing criminal charges have the right to legal representation once they are taken into custody or formally charged. If a defendant cannot afford an attorney, and the offense carries the possibility of jail time, they are entitled to a court-appointed attorney, often called a public defender. This right to counsel applies at all critical stages of a prosecution, including interrogations, arraignments, and trials.

What Are Your Eighth Amendment Rights?

The Eighth Amendment prohibits "excessive bail," meaning bail amounts cannot be unreasonably high. However, judges can deny bail altogether in certain circumstances. The Eighth Amendment also prohibits "cruel and unusual punishment." This means punishments must not be unnecessarily severe, arbitrarily applied, or offensive to generally accepted standards of decency. While the death penalty was once challenged under this amendment, it has been reinstated with specific procedural safeguards.

Stages of a Criminal Case

A criminal case may progress through several stages. Here’s a general overview of how it could unfold.

• Investigation and Arrest: If law enforcement develops probable cause that a specific person committed a crime, they may make an arrest. This may or may not involve a warrant.
• Formal Charges: This can happen through a criminal complaint filed by a prosecutor or an indictment from a grand jury (a group of citizens who review evidence and decide if there's enough to formally charge someone).
• Arraignment: The defendant appears in court, is informed of the charges, and enters a plea of guilty, not guilty, or no contest. Bail decisions are usually made at this stage.
• Pre-Trial Proceedings: These can include motions to suppress evidence (e.g., evidence obtained illegally) and discovery, where both sides exchange information relevant to the case. Some jurisdictions hold preliminary hearings to determine if there's enough evidence to proceed to trial.
• Trial: The prosecution must prove guilt "beyond a reasonable doubt." The defense can cross-examine prosecution witnesses and present its own evidence. Affirmative defenses, like self-defense, may be raised. If the jury can't agree on a verdict, the judge may declare a mistrial, and the prosecution can decide whether to retry the case.
• Sentencing: If the defendant is found guilty or pleads guilty, the court imposes a sentence. This can include prison, probation, fines, or other penalties. Sentences must comply with constitutional limits and applicable sentencing guidelines.
• Appeals: Defendants who believe legal errors occurred during their trial can appeal to a higher court. Appellate courts review the trial record. If they find significant errors that affected the outcome, they can order a new trial or other remedies.

Most cases don’t go all the way to trial, though. Instead, they end in plea bargains in which a defendant pleads guilty in exchange for some concessions by the prosecutor, such as dropping other charges or recommending reduced penalties.

Last reviewed February 2025