Summary of the Fourth Amendment

In 1788, the government ratified the United States Constitution. This document outlines the rights and obligations of U.S. citizens. Over the years, Congress has approved several amendments to the Constitution.

One of the most sacred protections of the Bill of Rights is the Fourth Amendment. This Amendment protects civilians' rights to liberty, property, and privacy. The Fourth Amendment also protects people from unreasonable search and seizure.

The following is a summary of the Fourth Amendment, including a brief history, the text of the Amendment itself, and how the Supreme Court defines its protections. This article will also offer examples of case law that explain some of the constitutional law decisions handed down over the years.

Background of the Fourth Amendment

In 1760, when Britain controlled the territories that would become the United States, the crown increased its control over trade by issuing "writs of assistance." Colonial smugglers were trading with and enriching the enemies of England. Their smuggled goods avoided taxation, which shortchanged the English treasury.

As a result, the British implemented the "writs of assistance" as a blanket warrant to enter any ship, building, or home to search (and seize, if necessary) any suspicious goods in colonial ports.

This action angered many colonists who saw it as an overreach — an "unreasonable" search and seizure. Several states instituted protections against these unreasonable searches and seizures in their constitutions before ratifying the U.S. Constitution's Fourth Amendment.

The courts first said the Fourth Amendment related to evidence in a criminal matter in Boyd v. United States in 1886. Interestingly, the Fourth Amendment did not initially apply to the states. This only happened once it was incorporated via the Fourteenth Amendment. The landmark Supreme Court case on this point was Mapp v. Ohio in 1961.

Summary of the Fourth Amendment

The Fourth Amendment is very brief. Despite its importance, it's only one sentence long. It has two clauses: the "unreasonable search and seizure" clause and the "warrants" clause.

The text of the Fourth Amendment reads as follows:

"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."

When John Adams, James Madison, and the other creators of the Constitution first drafted the Bill of Rights, they had no idea how the criminal justice system would change. When the states ratified the Constitution, the courts followed common law, not federal and state statutes.

Over the decades, the courts have continued to provide more details about how and when these protections apply. The courts must protect national security and other government interests, but they must also ensure that the courts afford defendants due process. They also demand law enforcement officials act in good faith when conducting searches, seizures, and lawful arrests.

Uncertainty Over the Text

Although ratification of the Fourth Amendment answered any lingering questions about the validity of the writs of assistance in the United States, the Fourth Amendment text raised questions of its own.

There was great debate over the intended meaning of the terms "unreasonable," "search or seizure," "warrant," "particularity," "oath or affirmation," and "probable cause." Congress also questioned the scope of protection offered for "houses, papers, and effects."

The U.S. Supreme Court, lower federal courts, district courts, appellate courts, and state courts have spent more than 230 years grappling with the questions raised by the Fourth Amendment's text and continue to do so as new cases come before them. For example, consider the challenges presented by new technology — thermal imaging, drone technology, metadata, etc. There are always new boundaries to explore.

Over the years, courts have clarified the rights protected by the Fourth Amendment. For example, the Supreme Court ruled that people have a reasonable expectation of privacy in their bodies, clothing, and personal belongings. Similarly, homeowners have a privacy interest that extends from their homes to the surrounding area, called curtilage.

Deciding where to draw the line on privacy and determining how to apply the rights to criminal procedure are still debated by state courts and the Supreme Court today. FindLaw has a more extensive discussion if you want to learn more about court decisions about Fourth Amendment protections.

What Is a Search and Seizure?

When most people hear the phrase "search and seizure," they envision somebody coming into their home and searching for proof that they engaged in criminal activity. But when the Constitution protects people against unreasonable search and seizure, it refers to any action by a law enforcement officer that involves a search of your person or property.

For example, if you are walking down the street and a police officer stops you and frisks you for weapons, that is a search. If they take any items during the search, it is a seizure.

A search and seizure also happens when a police officer enters your home or business and searches for items within the structure.

According to the Fourth Amendment to the Constitution, any search and seizure must be reasonable and justified.

Question of Reasonableness

When a law enforcement officer searches for your home or person, they must do so in a reasonable manner. They must limit their search to places that reasonably contain the object they are searching for.

When the court determines whether a search and seizure was reasonable, it will ask if a reasonable person would have believed that a crime had happened. It will also consider if a reasonable person, given the circumstances, would think that an instrument of the alleged crime happened in the place to be searched.

Probable Cause

Before a police officer can execute a search and seizure, they must determine that probable cause exists. Probable cause requires the following:

  • Law enforcement officials have a reason to believe that a crime happened, and
  • The person to be searched or arrested committed the crime, or that evidence of the crime is at the location to be searched

The police officer must have more than mere suspicion that a crime took place. They must make their decision based on facts and knowledge, that is:

  • Specific
  • Objective
  • Articulable

When a judge considers whether a search was reasonable, they must consider the totality of the circumstances. They must examine what the police officer knew during the search and seizure. They must also ask themselves if a reasonable person, given the same facts and knowledge, would have believed a crime happened and that the person arrested committed it. The officer must lay these facts out for the magistrate upon issuance of the warrant.

Reasonable Suspicion Is Not Enough

The Supreme Court clarified that law enforcement needs more than mere suspicion before they search. This is especially true for warrantless searches. The police officer must have the knowledge and facts necessary to support a finding of probable cause.

Reasonable suspicion is a standard slightly below probable cause. According to the courts, reasonable suspicion exists when a police officer has a reasonable and objective belief that a suspect committed a crime, is committing a crime, or is about to commit a crime.

This is the standard the Supreme Court has ascribed to "stop and frisk" situations.

Search Warrant Requirements

Almost all searches and seizures need a warrant. In nearly all cases, the police must have either a search warrant or an arrest warrant signed by a judge. The search warrant must specify that probable cause exists. It must also describe the facts surrounding the execution of the warrant.

There are certain situations in which a police officer or other member of law enforcement may execute a search and seizure without a warrant. These situations include:

  • Consent
  • Brief stop (stop and frisk)
  • Evidence of crime in plain view
  • Exigent circumstances

If the police conduct a warrantless search, they must justify their actions to the court. Your criminal law attorney can also challenge the search, arguing that the police violated your Fourth Amendment rights.

Consensual Search

Sometimes, the police receive consent to search a home, building, person, or vehicle. The person who consents to the search must have clear authority. For example, if a police officer knocks on a door and the person who answers confirms that they live there, the officer may gain consent from that person.

If the officer reasonably believes the person who gives consent has the power to consent, they can engage in a warrantless search. If the resident refuses to consent, the police must get a warrant. But, the officer is not required to tell the homeowner, resident, or guest they can deny consent.

Stop and Frisk

Over the years, many defendants have complained that the police stopped them and searched them without probable cause. In Terry v. Ohio, the Supreme Court determined that the police do not need probable cause to stop and frisk a suspect.

The officer must only have reasonable suspicion that a suspect committed or is about to commit a crime. Police must show they have the facts and knowledge to support their suspicion.

During a stop and frisk, the officer may only search the suspect for weapons. They are not allowed to search them for drugs or other paraphernalia.

Plain View Doctrine

If a police officer sees an item in plain view, they have the right to seize it. According to the Supreme Court in Harris v. U.S., as long as the officer has a right to be where they view the object, they can legally seize it.

The courts base this rule on the common-sense principle that you cannot expect people to ignore what is right in front of their faces. The officer does not need probable cause to seize evidence found in plain view.

Exigent Circumstances

The courts have held that the police can execute warrantless search and seizure under exigent circumstances. These circumstances exist in the following situations:

  • The suspect may escape
  • To prevent harm to a police officer or others
  • To preserve evidence that the suspect or related party may destroy
  • Any other circumstances that may frustrate the ability of law enforcement to carry out their legitimate duties

Suppose the police conduct a warrantless search of your person or property, and you do not feel they had justification to do so. You should contact a criminal law attorney immediately. This is especially true if the police arrest you after the search.

Arrest vs. Detainment

Legally, an arrest is a seizure under the Fourth Amendment. But, if the police merely detain you, it may not constitute a seizure. Thankfully, ample case law addresses the difference between arrest and detainment.

Detainment is when police stop a suspect and temporarily detain them for questioning or an investigation. For example, imagine that somebody robbed a convenience store. You are walking by the store when the police arrive. If they stop you to ask if you saw anything or participated in the robbery, that is detainment.

When the police detain a person, they do not need probable cause. They only need a reasonable suspicion that the person participated in the crime or had pertinent information about it.

The police make an actual arrest when they take you into custody based on the belief that you committed a crime. The officers typically handcuff you, read your Miranda rights, and take you to the police station or local jail. The police must have probable cause to arrest a suspect.

Vehicle Searches

One situation that has raised many questions happens when the police search your vehicle. Vehicle searches have seen a lot of attention from the courts. These searches are subject to the protections offered by the Fourth Amendment. But this does not mean the police need a warrant to search your car, truck, or SUV.

Police may do a warrantless search of your vehicle in certain situations. These include:

  • You consent to the search
  • The officers have probable cause to believe there is evidence of a crime in your vehicle
  • Evidence of a crime is in plain view
  • The officer has reason to believe there is a weapon in the vehicle that threatens the safety of the officers or others
  • A search incident to an arrest

You have the right to refuse to let the police search your car. Just know that they may proceed with the search anyway and seize any evidence they find. Your criminal law attorney can challenge the search later. The court will deem any evidence recovered in an unlawful search inadmissible.

The rules for searching a vehicle are less strict than those for searches of a home or other building. People expect less privacy in their cars than in their homes or businesses.

Electronic Surveillance and Wiretaps

Wiretapping is an example of a search and seizure. Technically, any information taken through a wiretap or other eavesdropping mechanism is evidence, and the state can use it against you. But, there are strict rules about electronic surveillance and wiretapping.

Not only are there federal wiretapping laws, but almost all states also have wiretap laws. For example, according to New York Penal Code Section 250, it is illegal to use a mechanical wiretap unless you have the consent of at least one of the parties to the conversation. This is the law in most states. In some states, you need the consent of both parties to record a telephone conversation.

If the state launches a criminal prosecution against you and introduces evidence recovered as a result of electronic surveillance or wiretapping, your attorney can challenge the admissibility of that evidence.

Exclusionary Rule

The point of requiring law enforcement to refrain from engaging in illegal searches and seizures is to protect would-be defendants. If the state uncovers evidence in an unlawful investigation, it cannot use that evidence in court. (This does not necessarily mean the state cannot use this evidence to secure a grand jury indictment).

Under the exclusionary rule, the judge must exclude evidence recovered during an illegal search and seizure. The rationale is that had the police officers honored your Fourth Amendment rights, they would not have found the evidence in the first place.

Fruit of the Poisonous Tree

One doctrine that falls under the exclusionary rule is the "Fruit of the Poisonous Tree" doctrine. According to this rule, the courts must exclude any evidence that is a by-product of an illegal search.

The best way to describe the "Fruit of the Poisonous Tree" doctrine is to envision a tree. The trunk and main branches represent the illegal evidence found during the initial search. The tree's smaller branches, leaves, and fruits are tainted or poisoned. Police would only have uncovered this evidence if law enforcement had performed the illegal search. So, the judge must throw out the fruit on that tree.

Protect Your Fourth Amendment Rights: Talk to an Attorney

Police can't search you and seize your property whenever they please. But sometimes, a search isn't considered a "search" under constitutional protections. At the same time, the law doesn't give members of law enforcement the right to violate your constitutional rights.

If you believe you have been the victim of a Fourth Amendment violation, contact an experienced criminal defense attorney near you today.

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