Search and Seizure Law

The Fourth Amendment to the U.S. Constitution prevents illegal searches and seizures. The protection against unlawful search & seizure is one of the most fundamental rights guaranteed to Americans. Although this is a fundamental right, search and seizure laws still have plenty of exceptions. It pays to understand how and when the police may search and seize your property.


This article highlights your constitutional rights under the Fourth Amendment and discusses search and seizure law.

The Fourth Amendment: Search and Seizure Law

The Fourth Amendment to the United States Constitution guarantees the following rights:

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.

The key word to notice here is "unreasonable." While the United States Constitution protects Americans from intrusive government searches and seizures, government officers can perform many reasonable searches and seizures without a warrant.

Whether a police search or seizure is reasonable depends primarily on whether you had a reasonable expectation of privacy in the first place.

Your Expectation of Privacy

Citizens are only protected from unlawful search and seizure when they have a legitimate expectation of privacy. In other words, if you didn't expect the place the police search to be private, law enforcement can search that area without a search warrant.

In Katz v. United States, the Supreme Court established a two-part test to determine if a person has a legitimate and reasonable expectation of privacy:

  • Did you actually expect some degree of privacy? Note that this is an actual test. Your criminal defense lawyer must demonstrate that you, in this particular instance, really did expect the place searched to be private. It is not enough that you might or often expect privacy.
  • Is your expectation of privacy objectively reasonable? The second part of the test requires that a reasonable person, in similar circumstances, would also have an expectation of privacy. For example, most people believe their purses and backpacks are private. However, if you have evidence of a crime on your front porch, you cannot expect the court to rule that you have a reasonable expectation of privacy.

Privacy and Reasonableness

The Fourth Amendment allows for a reasonable search & seizure, and reasonableness turns on expectations of privacy. Therefore, most criminal cases turn on whether society, represented by a jury, would agree that a person had an objectively reasonable expectation of privacy.

There are no hard and fast rules. However, there are common situations where the court may question whether an expectation of privacy exists:

  • Homes: The notion that a man's home is his castle has a long history of support in the American legal system. Very few instances exist where a person does not have a reasonable expectation of privacy in their home. Therefore, the police are almost always required to have a search warrant if they want to search and seize items inside your house. This expectation of privacy extends to hotel rooms as well. This is the case unless there are exigent circumstances.
    For example, if the police believe there is contraband inside the house that poses a threat to law enforcement, they may bypass the warrant requirement. Another example of a situation where the police do not need a warrant will be if they believe the suspect will destroy evidence before the police obtain a search warrant.
  • Automobiles: Cars have routinely been given a lowered expectation of privacy in the U.S. Even if you think you have a right to privacy in your car, the courts will likely disagree. Never bring anything into your vehicle you wouldn't mind the police seeing.
  • Bags, Purses, and Briefcases: Generally, courts have been willing to uphold a person's expectation of privacy in their bag, purse, or briefcase. This includes a see-through bag carried by a passenger on a public bus.

There have been many criminal law cases where defendants thought they had a right to privacy, but the courts disagreed. For example, in California v. Greenwood, the court held that a warrantless search of a person's garbage was legal. Even though most people conceal waste in a bag and typically place it in a canister, courts have regularly allowed police to search through it. As long as the suspect leaves the trash at the curb for collection, law enforcement officers can seize it.

Another example of something you would assume carries an expectation of privacy is an envelope. Many people expect the contents of envelopes to be inherently private. However, many courts have found that searches and seizures of the contents of envelopes were reasonable.

The Fourth Amendment Only Protects You From Governmental Searches and Seizures

An important distinction to note is that the Fourth Amendment protects you from the government, not from private individuals. The most common example is when security personnel asks or demands to search your belongings.

While the police may be unable to rummage through your purse, a mall cop can. If the mall cop finds illegal drugs or other evidence of criminal activity, they can turn you over to the police. The judge will likely rule any evidence the mall cop finds as admissible. Essentially, a security guard can do what a police officer can't.

It is important to mention that there are times when security personnel cannot conduct a warrantless search. For example, if a security agent is working on behalf of the government, they would be held to the same standard as an ordinary police officer.

Illegally Obtained Evidence

If the police conduct an illegal search, what happens to the evidence they find during the search? Evidence found during an unlawful search and seizure is generally deemed inadmissible in court under the exclusionary rule.

In Mapp v. Ohio, the U.S. Supreme Court held that the State cannot use evidence seized during an illegal search. This means that even if the police find a murder weapon and can conclusively establish that you killed someone, they cannot use this evidence to prove murder. If the police discovered it during an unlawful search and seizure, it is generally not admissible.

Fruit of the Poisonous Tree

Another rule that addresses the use of evidence obtained during an unlawful warrantless search is the "fruit of the poisonous tree" doctrine. This rule states that judges must exclude evidence obtained as a by-product of an illegal search.

For example, imagine the police have a reasonable belief that you are selling illegal drugs. They conduct a warrantless search of your house and find a map showing where you keep your illicit stash. The map and any information gleaned from the map are inadmissible because the initial search was unlawful.

Another example where the fruit of the poisonous tree doctrine applies is when the police seize your cell phone during an unlawful search. They find texts on the phone that substantiate the criminal charges against you. If the court deems the initial search illegal, the prosecution cannot use the evidence found on your phone.

It may seem like criminals often get away with crimes due to illegal search and seizures, but this happens much less often than you may think. There are several exceptions to the exclusionary rule and the fruit of the poisonous tree doctrine. Some of these exceptions include:

  • Inevitable detection: If the police can prove that they would've found the evidence regardless of the illegal search, the judge may allow the State to use the evidence in court.
  • Plain View: If the police find evidence in plain view while making a lawful arrest, the evidence will likely be deemed admissible. For example, if the police conduct a traffic stop for DUI and see an open container or drug paraphernalia on the center console, they can seize these items.
  • Exigent Circumstances: One common exception cited by the prosecution is that the police conducted a search due to exigent circumstances. For example, imagine the police go to a suspect's home with an arrest warrant. The defendant yells out from an upstairs window that they have a gun and are willing to use it. Law enforcement officers must protect themselves and others from injury or death. In this case, the police could enter the home and search the premises.
  • Consensual Searches: The police do not need a valid search warrant if a suspect consents to a legal search. Anybody with apparent authority to grant permission can provide consent.
  • Searches Incident to a Lawful Arrest: The police can conduct a search incident to arrest.
  • Stop and Frisk: If an officer has reasonable suspicion to believe an individual committed a crime or has information about it, they can briefly detain them. They have the right to frisk the individual if they suspect the person has a weapon or evidence of the offense the police are investigating.

As you can see, the protections afforded by the Fourth Amendment are not limitless. If the State charges you with a misdemeanor or felony, you should contact a local attorney's law office.

Protect Your Fourth Amendment Rights: Meet With an Attorney

As you can see, there are significant restrictions on what law enforcement can do when searching you or your property and seizing evidence. If a search or seizure is deemed unlawful, it could exclude critical evidence at trial. This can make a significant difference in your case.

The key is to have an experienced criminal defense attorney by your side. Consider speaking with a lawyer and putting their expertise to work for you.

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