The Fourth Amendment and the 'Exclusionary Rule'

When first ratified, the Fourth Amendment was of little value to criminal defendants. The framers of the U.S. Constitution were not concerned with criminal defendants' rights. Until the early 20th century, evidence seized by law enforcement in violation of the Fourth Amendment was still admissible in court. The court's position changed in 1914.

The Fourth Amendment to the U.S. Constitution prohibits police officers from conducting unreasonable searches and seizures. It requires law enforcement to have a valid warrant or probable cause. But what happens if a police officer performs a search in violation of the Fourth Amendment and finds incriminating evidence? That's when the exclusionary rule comes into play.

Read on to learn how this rule developed and why we have it in the first place.

The Development of the Exclusionary Rule

In 1914, the U.S. Supreme Court dramatically changed the Fourth Amendment when it handed down its decision in Weeks v. United States. This case involved the appeal of a defendant convicted based on evidence a federal agent seized without the issuance of a warrant or other constitutional justification. The Supreme Court overturned the conviction, creating the exclusionary rule. In 1961, the U.S. Supreme Court made the exclusionary rule applicable to the states with its decision in Mapp v. Ohio.

The court in Mapp v. Ohio also confirmed that the exclusionary rule applies to state law through the Fourteenth Amendment. Some states, such as New York, offer even greater protection than the federal government on the exclusionary rule.

Not all countries follow the exclusionary rule. Under the common law, jurisdictions could set their own rules about the admissibility of tainted evidence. For example, in England, the courts follow an inclusionary rule. Prosecutors can use evidence regardless of whether law enforcement officials got it illegally.

Why Do We Have the Exclusionary Rule?

The courts created the exclusionary rule to deter police misconduct. It enables courts to exclude incriminating evidence from trial if the defendant can prove the police got the evidence in violation of a constitutional right.

The rule allows defendants to challenge the admissibility of evidence by bringing a pre-trial motion to suppress the evidence. If the court allows the evidence and the jury votes to convict, the defendant can challenge the trial court's decision to deny the motion to suppress on appeal.

If the defendant succeeds on appeal, they can get a new trial. The U.S. Supreme Court has ruled that double jeopardy principles do not bar another trial because the trial court's error had nothing to do with the defendant's guilt or innocence. Nonetheless, obtaining a conviction in the second trial would be significantly more challenging if the evidence suppressed by the exclusionary rule is vital to the prosecution's case.

Companion to the Exclusionary Rule: Fruit of the Poisonous Tree

The "fruit of the poisonous tree" doctrine is a legal concept related to the exclusionary rule. Under this doctrine, a court may exclude evidence seized in an unlawful search and seizure and other evidence derived from the illegal search.

For example, suppose the police arrest a suspect for kidnapping, and the suspect later confesses to the crime. If a court later declares that the arrest was unconstitutional, the judge must also rule that the confession is inadmissible. The defendant's criminal law attorney will argue that police denied their client due process as a result of the violation of their Fourth Amendment rights. The attorney may also be able to prove that they violated the defendant's Fifth Amendment protection against self-incrimination.

Common Examples of Tainted Evidence

When law enforcement recovers illegally obtained evidence, the court will deem it "tainted" evidence. Tainted evidence includes any physical evidence, DNA, audio recording, contraband, or other evidence taken during a warrantless search. The judge will order suppression of evidence unless law enforcement officers can prove that a good faith exception applies in a particular case.

Some of the more common examples of tainted evidence include:

  • A wiretap recording between two defendants that the police seized without a search warrant
  • A confession that the police got using force, duress, or coercion
  • DNA that law enforcement took without a warrant

When suppressing evidence, the courts consider the totality of the circumstances. The warrant requirement is important. But if the judge believes the police acted in good faith, they may allow the prosecutor to use the evidence during the criminal trial.

Illegal Searches During a 'Stop and Frisk'

One common situation where the right of the people challenges the right of the state involves the "stop and frisk." Police officers stop and frisk suspects all the time. This happens a lot for officers who walk the beat. It is also something they do when they arrive at a crime scene.

If law enforcement believes a person may have had something to do with a crime, it has the right to detain them. If they think the suspect has a weapon, they can frisk the person. The question is whether this counts as a search.

According to the Supreme Court in Terry v. Ohio, it is constitutional to stop and frisk a person the police reasonably believe to be armed and involved in a crime. In this case, two men stood outside a store, supposedly casing the place. The police approached them and did a pat-down. They found guns on both suspects. Police arrested the two men and charged them with carrying illegal, concealed weapons.

One of the defendants, John W. Terry, argued that the judge had to throw out the evidence against him. His defense attorney argued that police took the evidence during an illegal search. The judge denied his motion.

The defendant was then convicted. Terry appealed, but the Court of Appeals in Ohio denied his request. The defendant then filed a motion with the Supreme Court, and the court agreed to hear his case. The Supreme Court affirmed the lower court's ruling. All but one of the justices agreed with this ruling. Justice William O. Douglas issued a dissenting opinion where he argued that the police shouldn't stop and search a suspect without probable cause.

The 'Good Faith' Exception

There is another general exception called the Good Faith exception. According to this rule, some evidence recovered during an unreasonable search can be used at trial if the police acted in good faith.

In 1984, the Supreme Court established the good faith exception in United States v. Leon. In this case, the police had received a tip that two people were running an illegal drug operation out of their homes. The police conducted surveillance of the suspects' homes and vehicles. Between what the police found and information they received from an informant, the police drafted an affidavit requesting a warrant.

The judge issued the warrant based on the information provided in the affidavit. The court later learned that the information the police provided the magistrate was inaccurate. The defendant demanded that the evidence be inadmissible. The court ruled that the state could use the evidence at trial.

The rationale of the chief justice and concurring justices was that the courts designed the exclusionary rule to deter police misconduct. They did not create the rule to punish judges or the police for errors. The ruling in United States v. Leon gave rise to the more general good faith exception cited in many criminal cases today.

Challenging the Use of Evidence Seized During an Unlawful Search

The judge will not automatically toss out evidence recovered during a warrantless search. Whether your trial is in federal or state court, your defense attorney must object to the state's use of this evidence.

If your defense attorney wants the judge to deem specific evidence inadmissible, they must file a motion. This motion must identify the evidence the defendant wants the judge to throw out. It must also state why the evidence is inadmissible. The motion must spell out the police conduct that led to the discovery of the evidence.

The state will then have a chance to explain why the evidence should be allowed. For example, the prosecutor may argue that exigent circumstances existed at the time of the search. Or the prosecution team may claim that the evidence was in plain view of law enforcement officers. Once the judge hears both sides, they decide whether to exclude the seized evidence.

In some cases, your defense attorney must show that you had a legitimate expectation of privacy during the search. Just because the police search your personal property does not mean it is an illegal search.

In Rakas v. Illinois, the court found that a defendant must show that they have a legitimate and reasonable expectation of privacy where police searched.

Learn More About the Fourth Amendment and the Exclusionary Rule: Speak with an Attorney

If you're facing criminal charges, the exclusionary rule may help determine the outcome of your criminal case. But, courts do not automatically exclude evidence unlawfully seized by law enforcement.

Your defense attorney must look at the evidence and make the appropriate objections. They can also challenge the use of evidence collected during an unconstitutional search before your criminal trial.

These issues can become complicated, especially if you are representing yourself. That's why having a strong criminal defense lawyer is critical from the very start of your case.

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