Exceptions to the Fourth Amendment Warrant Requirement

Most Americans know the constitutional safeguards against unreasonable searches and understand the importance of the warrant requirement in protecting Fourth Amendment rights. However, in evaluating the totality of the circumstances, the Supreme Court has outlined several nuanced exceptions to prevent the destruction of evidence.

The Foundation of Search Warrants

Courts view warrantless searches as a violation of the Fourth Amendment because they undercut one's reasonable expectation of privacy. The Fourth Amendment of the U.S. Constitution states:

"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."

Police officers can generally search and seize a person or evidence of a crime with a search warrant or an arrest warrant. A judge issues these warrants after showing probable cause, a reasonable belief of the arrestee's criminal activity. Warrantless searches may lead to the exclusion of evidence, so law enforcement must obtain a warrant, where possible, absent a valid exception.

Criteria for a Valid Search Warrant Under the Fourth Amendment

A neutral judge or magistrate may issue a search warrant upon receiving a sworn affidavit from law enforcement. The affidavit should detail the police officer's observations made in good faith or those from a credible informant, asserting that the suspect has committed a crime. It should also state that evidence of this crime will likely be discovered in a specified location or by seizing the suspect's property.

Probable cause is the cornerstone of the search warrant. The search warrant is invalid if it is not grounded in a reasonable belief or fact that justifies the suspicion. Additionally, criminal defense lawyers will attack the vagueness of the warrant if it is not specific. The search warrant is not a blank cheque; it must include the exact place the police want to search and the items to seize.

For example, let's say police officers respond to a domestic violence call and observe illegal marijuana plants growing in a neighbor's open garage. Here, the police officer may submit a sworn affidavit regarding his observations and request a search warrant for the garage to seize the illegal marijuana plants. The police officer cannot use the search warrant to search the suspect's basement because the parameters limit the range of the search to the garage.

Obtaining a warrant is not always feasible, especially in situations where it could result in the destruction of evidence.In the example above, if police officers leave to get a warrant, the neighbor may subsequently remove the illegal marijuana plants or destroy them. Below, we discuss the limited circumstances where a search warrant is unnecessary.

Exceptions to the Warrant Requirement

The Supreme Court has identified six narrow exceptions where a warrantless search is reasonable and will not result in the exclusion of evidence obtained therein. These include:

• Exigent circumstances
• Plain view
• Search incident to arrest
• Consent
• Automobile exceptions
• Special needs 

We will explore these exceptions in greater detail in the following sections.

The Exigent Circumstances Exception 

Law enforcement often responds to emergencies that may threaten public safety. In such situations, it is impractical to submit a warrant application where the delay could lead to substantial bodily harm, death, or destruction of evidence.

In Warden v. Hayden, officers pursued a suspect in an armed robbery into a private home. The officers, in hot pursuit, entered the home without a warrant. Still, the Court found the situation permitted the warrantless entry and search. 

The Plain View Exception

In the course of their daily duties, police officers may observe contraband in plain view. In Washington v. Chrisman, the Court found when evidence is in sight of law enforcement officers who are lawfully present, they may search or seize the contraband without a warrant.

For example, let's say police officers respond to a noise complaint. Upon their arrival, they observe drug paraphernalia and what appear to be illegal substances on a student's desk in their dorm room. They can confiscate those items without a warrant. 

Police officers executing a valid arrest warrant may also seize evidence of other crimes they observe in plain view.

For example, in Maryland v. Buie, officers entered a home with a valid arrest warrant for two robbery suspects. One officer conducted a protective sweep of the basement after one suspect emerged in case someone else hid there. This officer observed and seized clothing that matched one of the robbery suspects and was in plain view. Although the officers did not have a search warrant, the Court allowed the admission of the clothing.

Search Incident to a Lawful Arrest

The Supreme Court has ruled it is reasonable for officers to search an arrestee to ensure officer safety from concealed weapons and prevent evidence destruction. This search incident to arrest extends to the arrestee's wingspan, which the Court clarified in Chimel v. California to mean the area within the arrestee's immediate control.

For example, a robbery suspect who used force or threat of force to take someone else's property unlawfully may have the bag they're carrying at the time of their arrest searched for concealed weapons such as a knife. 

However, this doctrine does not allow officers to search an arrestee's digital information, such as a cell phone or computer, without a warrant. The Court found in Riley v. California that digital evidence does not pose the same threat to officer safety as a weapon. Additionally, the concern regarding the destruction of evidence is less immediate, given the seizure of electronic devices. 

The evolving nature of Fourth Amendment interpretations by the U.S. Supreme Court further limits law enforcement.

For example, in Terry v. Ohio, the Court clarified that police officers can only stop a person if they have a reasonable articulable suspicion of criminal activity. In that case, the police officer observed two men walking the same route and staring into the same storefront 24 times. The officer suspected the men were "casing a job" to rob the store. The officer followed the men and subsequently stopped and conducted a pat-down search of their outer clothing. 

The Court held that this limited stop and frisk for weapons was reasonable to ensure officer safety. This type of investigative stop is known as a Terry stop. It is only justified by reasonable facts that point toward suspicious conduct or a belief in criminal activity, not just a hunch. 

Consent Searches

Criminal suspects can voluntarily waive their Fourth Amendment rights and consent to a search of their person or property without a warrant. However, it is common that more than one person may reside at the suspect's home, so issues have arisen regarding who can validly consent to a search in a shared property. 

For example, suppose the police conduct a drug raid and have a search warrant for the minor suspect's bedroom. In that case, his parents may consent to a search of the whole home, including shared spaces such as the attic or basement. In United States v. Matlock, the Court permitted evidence obtained with the permissibility of one co-occupant in the other's absence. 

However, the Court distinguished Matlock in Georgia v. Randolph. Here, the defendant's estranged wife consented to a search of the marital residence despite the defendant's refusal.

The Court found that the waiver and consent were unreasonable where a co-occupant was physically present and unequivocally refused the warrantless entry. So, the warrantless search was not reasonable, and evidence of drug use obtained after that was inadmissible.  

The Automobile Exception

The Court has found a lesser expectation of privacy on the roads where police may conduct traffic stops or roadside checkpoints if they have a reasonable suspicion of a crime occurring. 

For example, police may stop a speeding driver in a school zone, which typically has lower speed limits, to ensure the safety of minor children. Upon stopping a speeding driver, police may develop probable cause that the driver is driving under the influence if they smell alcohol or marijuana or see an open liquor bottle in plain view. In this case, the police can search the motor vehicle's interior and seize any contraband found. 

In New York v. Belton, the Court allowed a vehicle search incident to arrest, including a search of the passenger compartment and containers, even after the occupants were ordered out of the vehicle. The police officers stopped a speeding car. The officer who approached the window caught the smell of burnt marijuana and saw an envelope they suspected contained further contraband. The officer ordered all the occupants to get out of the car and then searched the passenger compartment as well as unzipped a jacket pocket, where the officer discovered cocaine.

However, in Arizona v. Gant, the Court distinguished New York v. Belton. The Court found that police may search the passenger compartment only if it is reasonable to believe the suspect could access it to hide evidence and that it is within the suspect's reach at the time of the search, not after securing the scene.

The Special Needs Doctrine 

There are a few exceptions where the Court recognizes the government's interest in public safety is more important than one's privacy. This extends beyond the normal purposes of law enforcement and may also apply to national security. Examples where the special needs doctrine may apply include searches conducted at:

• Public safety checkpoints such as borders
• Drug testing and searches of prisoners, parolees, and probationers
• School and workplace searches

Protecting Against Fourth Amendment Violations

There is a dynamic balance between law enforcement needs and protecting constitutional rights. So, the Supreme Court introduced the exclusionary rule as a remedy for warrantless searches not covered by any of the exceptions listed above. Under this rule, evidence obtained through an unlawful search is inadmissible at trial against the criminal defendant. 

Understanding one's rights and the limitations of law enforcement is critical. Defendants can contest the validity of a warrantless search by challenging the voluntariness of the consent, whether the totality of the circumstances qualified as an emergency, or the scope of the search, such as police opening a trunk without probable cause.